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Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

International Rectifier Power Control Systems | Open Energy Information  

Open Energy Info (EERE)

Rectifier Power Control Systems Rectifier Power Control Systems Jump to: navigation, search Name International Rectifier Power Control Systems Place El Segundo, California Zip 90245 Product Originally a division of International Rectifier Corporation manufacturing semiconductor and module components for power management products. References International Rectifier Power Control Systems[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. International Rectifier Power Control Systems is a company located in El Segundo, California . References ↑ "International Rectifier Power Control Systems" Retrieved from "http://en.openei.org/w/index.php?title=International_Rectifier_Power_Control_Systems&oldid=347055"

2

Phase controlled rectifier circuit for rapidly charging batteries  

SciTech Connect

An improved battery charger circuit for rapidly charging a battery by increasing the rate of battery charge acceptance through periodic battery discharge during the charging process includes a pair of first and second controlled rectifier circuits coupled to an ac source and adapted for coupling to a battery. The first controlled rectifier circuit is rendered conductive during the charging intervals to supply the battery with charge current from the ac source. The second controlled rectifier circuit is rendered conductive during battery discharge intervals to discharge the battery in a substantially lossless manner by conducting battery discharge current through the ac source, thus realizing a highly efficient battery charger.

Steigerwald, R. L.

1981-02-24T23:59:59.000Z

3

Single-Phase Active Boost Rectifier with Power Factor Correction for Wireless Power Transfer Applications  

SciTech Connect

Wireless Power Transfer (WPT) technology is a novel research area in the charging technology that bridges utility and the automotive industries. There are various solutions that are currently being evaluated by several research teams to find the most efficient way to manage the power flow from the grid to the vehicle energy storage system. There are different control parameters that can be utilized to compensate for the change in the impedance. To understand the power flow through the system this paper presents a novel approach to the system model and the impact of different control parameters on the load power. The implementation of an active front-end rectifier on the grid side for power factor control and voltage boost capability for load power regulation is also discussed.

Chinthavali, Madhu Sudhan [ORNL; Onar, Omer C [ORNL; Miller, John M [ORNL; Tang, Lixin [ORNL

2013-01-01T23:59:59.000Z

4

Digital multimode buck converter control with loss-minimizing synchronous rectifier adaptation  

E-Print Network (OSTI)

Abstract—This paper develops a multimode control strategy which allows for efficient operation of the buck converter over a wide load range. A method for control of synchronous rectifiers as a direct function of the load current is introduced [1]. The function relating the synchronous-rectifier timing to the load current is optimized on-line with a gradient power-loss-minimizing algorithm. Only low-bandwidth measurements of the load current and a power-loss-related quantity are required, making the technique suitable for digital controller implementations. Compared to alternative loss-minimizing approaches, this method has superior adjustment speed and robustness to disturbances, and can simultaneously optimize multiple parameters. The proposed synchronous-rectifier control also accomplishes an automatic, optimal transition to discontinuous-conduction mode at light load. Further, by imposing a minimum duty-ratio, the converter automatically enters pulse-skipping mode at very light load. Thus, the same controller structure can be used in both fixed-frequency pulsewidth modulation and variable-frequency pulse-skipping modes. These techniques are demonstrated on a digitally-controlled 100-W buck converter. Index Terms—Adaptive control, dead-time, digital control, gradient methods, multimode control, optimization methods, pulse skipping, pulsewidth modulated (PWM) power converters, pulsewidth modulation (PWM), synchronous rectifier (SR), variable frequency control. Fig. 1. Buck converter with SR (M), and the corresponding MOSFET control signals.

Angel V. Peterchev; Seth R. S

2006-01-01T23:59:59.000Z

5

New single-switch three-phase high power factor rectifiers using multi-resonant zero current switching  

E-Print Network (OSTI)

Abstract — A new family of single-switch three-phase highpower-factor rectifiers, which have continuous input and output currents, is introduced. By using a multiresonant scheme, the transistor operates with zero-current switching (ZCS), and the diodes operate with zero-voltage switching (ZVS). These multiresonant rectifiers with a single transistor are capable of drawing a higher quality input-current waveform at nearly unity power factor and lower stresses than quasi-resonant rectifiers. Buck-type converters are used for the power stage, and, hence, the output voltage is lower than the input voltage. Moreover, these rectifiers have a wide load range and low stresses on semiconductor devices. From the analysis, normalized characteristics of the rectifier are derived. The design and breadboard implementation of the rectifier delivering 147 V? ™ at 6 kW from a 30 240-V???@vvA input is described. The total harmonic distortion (THD) of the line current is less than 5%, and the system efficiency is about 94% at the full load. Index Terms — Frequency control, multiresonant, power factor correction (PFC), resonant converters, three-phase rectifiers,

Yungtaek Jang; Robert W. Erickson

1994-01-01T23:59:59.000Z

6

Autonomous induction generator/rectifier as regulated DC power supply for hybrid renewable energy systems  

Science Conference Proceedings (OSTI)

The present article deals with the wind power-generating unit of a Hybrid Photovoltaic-Wind Renewable Energy System (HPVWRES). The dynamic flux model of the self-excited induction generator used in the wind power-generating unit is given. This model, ... Keywords: experimental investigation, hybrid, induction generator, modeling, rectifier, regulation, renewable Energy

A. Nesba; R. Ibtiouen; S. Mekhtoub; O. Touhami; N. Takorabet

2005-10-01T23:59:59.000Z

7

Rectifier cabinet static breaker  

Science Conference Proceedings (OSTI)

A rectifier cabinet static breaker replaces a blocking diode pair with an SCR and the installation of a power transistor in parallel with the latch contactor to commutate the SCR to the off state. The SCR serves as a static breaker with fast turnoff capability providing an alternative way of achieving reactor scram in addition to performing the function of the replaced blocking diodes. The control circuitry for the rectifier cabinet static breaker includes on-line test capability and an LED indicator light to denote successful test completion. Current limit circuitry provides high-speed protection in the event of overload. 7 figs.

Costantino, R.A. Jr; Gliebe, R.J.

1992-09-01T23:59:59.000Z

8

Rectifier cabinet static breaker  

DOE Patents (OSTI)

A rectifier cabinet static breaker replaces a blocking diode pair with an SCR and the installation of a power transistor in parallel with the latch contactor to commutate the SCR to the off state. The SCR serves as a static breaker with fast turnoff capability providing an alternative way of achieving reactor scram in addition to performing the function of the replaced blocking diodes. The control circuitry for the rectifier cabinet static breaker includes on-line test capability and an LED indicator light to denote successful test completion. Current limit circuitry provides high-speed protection in the event of overload.

Costantino, Jr, Roger A. (Mifflin, PA); Gliebe, Ronald J. (Library, PA)

1992-09-01T23:59:59.000Z

9

Particle swarm optimisation for power quality improvement of a 12-pulse rectifier-chopper fed LCI-synchronous motor drive  

Science Conference Proceedings (OSTI)

This paper investigates the optimised passive filter combination for power quality improvement of a 12-pulse rectifier-chopper fed load commutated inverter LCI based synchronous motor SM drive. The search of optimised component values of passive filter ...

Sanjeev Singh; Bhim Singh

2012-03-01T23:59:59.000Z

10

A Multilevel Active Front-End Rectifier With Current Harmonic Compensation Capability  

E-Print Network (OSTI)

transformation. By controlling id and iq at the rectifier input side, the active and reactive power absorbed-q transformation requires a more complex hardware and software implementation. The power circuit topology-end rectifier that can absorb current harmonics generated by nonlinear loads connected to the same power

Rudnick, Hugh

11

Maximum power point tracker for solar arrays using controlled rectifier.  

E-Print Network (OSTI)

??M.S. Solar energy offers a large potential as a source of energy and in light of financial and ethical reasons, people are looking to harvest… (more)

Manadan, Anvin Joe, 1987-

2012-01-01T23:59:59.000Z

12

An efficient piezoelectric energy harvesting interface circuit using a bias-flip rectifier and shared inductor  

E-Print Network (OSTI)

Abstract—Harvesting ambient vibration energy through piezoelectric means is a popular energy harvesting technique which can potentially supply 10–100’s of W of available power. One of the main limitations of existing piezoelectric harvesters is in their interface circuitry. In this paper, a bias-flip rectifier circuit that can improve the power extraction capability from piezoelectric harvesters over conventional full-bridge rectifiers and voltage doublers by greater than 4X is implemented in a 0.35 m CMOS process. An efficient control circuit to regulate the output voltage of the rectifier and recharge a storage capacitor is presented. The inductor used within the bias-flip rectifier is shared efficiently with a multitude of switching DC-DC converters within the system reducing the overall component count. Index Terms—Bias-flip rectifier, DC-DC converter, full-bridge rectifier, inductor sharing, micropower, piezoelectric harvester.

Yogesh K. Ramadass; Anantha P. Ch

2010-01-01T23:59:59.000Z

13

Microwave and millimeter-wave rectifying circuit arrays and ultra-wideband antennas for wireless power transmission and communications  

E-Print Network (OSTI)

In the future, space solar power transmission and wireless power transmission will play an important role in gathering clean and infinite energy from space. The rectenna, i.e., a rectifying circuit combined with an antenna, is one of the most important components in the wireless power transmission system. To obtain high power and high output voltage, the use of a large rectenna array is necessary. Many novel rectennas and rectenna arrays for microwave and millimeter-wave wireless power transmission have been developed. Unlike the traditional rectifying circuit using a single diode, dual diodes are used to double the DC output voltage with the same circuit layout dimensions. The rectenna components are then combined to form rectenna arrays using different interconnections. The rectennas and the arrays are analyzed by using a linear circuit model. Furthermore, to precisely align the mainbeams of the transmitter and the receiver, a retrodirective array is developed to maintain high efficiency. The retrodirective array is able to track the incident wave and resend the signal to where it came from without any prior known information of the source location. The ultra-wideband radio has become one of the most important communication systems because of demand for high data-rate transmission. Hence, ultra-wideband antennas have received much attention in mobile wireless communications. Planar monopole ultra-wideband antennas for UHF, microwave, and millimeter-wave bands are developed, with many advantages such as simple structure, low cost, light weight, and ease of fabrication. Due to the planar structures, the ultra-wideband antennas can be easily integrated with other circuits. On the other hand, with an ultra-wide bandwidth, source power can be transmitted at different frequencies dependent on power availability. Furthermore, the ultra-wideband antenna can potentially handle wireless power transmission and data communications simultaneously. The technologies developed can also be applied to dual-frequency or the multi-frequency antennas. In this dissertation, many new rectenna arrays, retrodirective rectenna arrays, and ultra-wideband antennas are presented for microwave and millimeter-wave applications. The technologies are not only very useful for wireless power transmission and communication systems, but also they could have many applications in future radar, surveillance, and remote sensing systems.

Ren, Yu-Jiun

2007-05-01T23:59:59.000Z

14

Benzene rectifying column performance optimization  

Science Conference Proceedings (OSTI)

Benzene rectifying column control at the actual petroleum refinery is studied. Certain approaches to increase the performance of precise rectification of benzene and toluene are suggested. An algorithm of evaluating the optimal regulation parameters ...

D. A. Smirnova; V. I. Fedorov; N. V. Lisitsyn

2011-01-01T23:59:59.000Z

15

International Rectifier Corporation | Open Energy Information  

Open Energy Info (EERE)

Rectifier Corporation Rectifier Corporation Jump to: navigation, search Name International Rectifier Corporation Place El Segundo, California Zip 90245 Product Manufacturer of analog and mixed signal ICs, advanced circuit devices, integrated power systems and components that enable high performance of end products in home appliances, industrial motor-driven equipment, autos, and information technology. References International Rectifier Corporation[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. International Rectifier Corporation is a company located in El Segundo, California . References ↑ "International Rectifier Corporation" Retrieved from "http://en.openei.org/w/index.php?title=International_Rectifier_Corporation&oldid=347054"

16

Harmonic Amplitudes Calculation Method and Simulation of Diode-bridge Rectifier's Output Current  

Science Conference Proceedings (OSTI)

Taking the three-phase uncontrolled diode-bridge rectifier of a certain style armored vehicle’s power supple system as research object, a practical method to calculate the harmonic amplitudes of rectifier’s DC-side output current is theoretically ... Keywords: rectifier, harmonic amplitude, switching function, simulation, MATLAB

Wei Wei; Xiaojun Ma; Shuguang Wei; Zhaozhao He

2010-03-01T23:59:59.000Z

17

Future High Voltage Silicon Carbide Power Devices Future ...  

Science Conference Proceedings (OSTI)

... PFC) in Switch Mode Power Supplies (SMPS) • Anti-Parallel rectifier in Motor Control • Boost Converter and Inverter Section for solar conversion ...

2013-04-20T23:59:59.000Z

18

Performance of ECM controlled VAV fan powered terminal units  

E-Print Network (OSTI)

Empirical performance models of fan airflow, primary airflow and power consumption were developed for series and parallel variable air volume fan powered terminal units. An experimental setup and test procedure were created to test the terminal units at typical design pressures and airflows. Each terminal unit observed in this study used an 8 in (20.3 cm) primary air inlet. Two fan motor control methods were considered. The primary control of interest was the electronically commutated motor (ECM) controller. Data collected were compared with previous research regarding silicon rectified control (SCR) units. Generalized models were developed for both series and parallel terminal units. Coefficients for performance models were then compared with comparable SCR controlled units. Non-linear statistical modeling was performed using SPSS software (2008). In addition to airflow and power consumption modeling, power quality was also quantified. Relationships between real power (watts) and apparent power (VA) were presented as well as harmonic frequencies and total harmonic distortion. Power quality was recorded for each ECM controlled terminal unit tested. Additional tests were also made to SCR controlled terminal units used in previous research (Furr 2006). The airflow and power consumption performance models had an R2 equal to 0.990 or greater for every terminal unit tested. An air leakage model was employed to account for leakage in the parallel designed VAV terminal units when the internal fan was turned off. For the leakage model, both ECM and SCR controlled units achieved an R2 greater than or equal to 0.918.

Cramlet, Andrew Charles

2008-08-01T23:59:59.000Z

19

Design and Evaluation of a 42-V Automotive Alternator With Integrated Switched-Mode Rectifier  

E-Print Network (OSTI)

This paper presents techniques for the design of high-power Lundell alternators with integrated switched-mode rectifiers. A multisection stator winding and interleaved rectifier arrangement is introduced that enables high ...

Tang, Sai Chun

20

542 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 19, NO. 2, MARCH 2004 Analysis and Modeling of a Voltage Doubler Rectifier  

E-Print Network (OSTI)

Prof. Dr.-Ing. Joachim Böcker p RailCab Novel Modular Railway System Small autonomous vehicles Power Supply for Piezoelectric Actuators Characteristics of piezoelectric actuators High force, small for piezoelectric actuators 2-level or 3-level inverter topologies Compensation of the capacitive reactive power

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Stirling engine power control  

DOE Patents (OSTI)

A power control method and apparatus for a Stirling engine including a valved duct connected to the junction of the regenerator and the cooler and running to a bypass chamber connected between the heater and the cylinder. An oscillating zone of demarcation between the hot and cold portions of the working gas is established in the bypass chamber, and the engine pistons and cylinders can run cold.

Fraser, James P. (Scotia, NY)

1983-01-01T23:59:59.000Z

22

Improved performance alternator with fully integrated Switched-Mode Rectifier  

E-Print Network (OSTI)

The use of Power Electronic circuits has helped to advance the technology of automotive alternators. The use of a Switched-Mode Rectifier (SMR) allows the alternator to run at a load-matched condition, optimizing power and ...

Mesa, Armando

2008-01-01T23:59:59.000Z

23

Maximum power tracking control scheme for wind generator systems  

E-Print Network (OSTI)

The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor speed measurements as control variable inputs. The dependence on the accuracy of the measurement devices makes the controller less reliable. The proposed control scheme is based on the stiff system concept and provides a fast response and a dynamic solution to the complicated aerodynamic system. This control scheme provides a response to the wind changes without the knowledge of wind speed and turbine parameters. The system consists of a permanent magnet synchronous machine (PMSM), a passive rectifier, a dc/dc boost converter, a current controlled voltage source inverter, and a microcontroller that commands the dc/dc converter to control the generator for maximum power extraction. The microcontroller will also be able to control the current output of the three-phase inverter. In this work, the aerodynamic characteristics of wind turbines and the power conversion system topology are explained. The maximum power tracking control algorithm with a variable step estimator is introduced and the modeling and simulation of the wind turbine generator system using the MATLAB/SIMULINK® software is presented and its results show, at least in principle, that the maximum power tracking algorithm developed is suitable for wind turbine generation systems.

Mena Lopez, Hugo Eduardo

2007-12-01T23:59:59.000Z

24

6.334 Power Electronics, Spring 2003  

E-Print Network (OSTI)

The application of electronics to energy conversion and control; phase-controlled rectifier/inverter circuits, dc/dc converters, high-frequency inverters, and motion control systems. Characteristics of power semiconductor ...

Perreault, David John

25

Analysis of parametric transformer with rectifier load  

SciTech Connect

This paper describes a push-pull parametric transformer constructed using a pair of orthogonal-cores. The operating characteristics of the parametric transformer with a rectifier load were analyzed based on SPICE simulations. The analysis results show good agreement with experiment. It was found that the input surge current of the full-wave rectifier circuit with a smoothing capacitor can be compensated by the parametric transformer. Use of the parametric transformer as a power stabilizer is anticipated owing to its various functions such as for voltage regulation and overload protection.

Ichinokura, O.; Jinzenji, T. (Tohoku Univ., Sendai (Japan)); Tajima, K. (Akita Univ. (Japan))

1993-03-01T23:59:59.000Z

26

Power Management Controls  

NLE Websites -- All DOE Office Websites (Extended Search)

additional savings of 1.3 billion are lost because power management is present, but disabled. In some cases, power management is not compatible with the application or doesn't...

27

Flex power perspectives of indirect power system control through...  

Open Energy Info (EERE)

power perspectives of indirect power system control through dynamic power price (Smart Grid Project) Jump to: navigation, search Project Name Flex power perspectives of indirect...

28

Wireless scheduling with power control  

Science Conference Proceedings (OSTI)

We consider the scheduling of arbitrary wireless links in the physical model of interference to minimize the time for satisfying all requests. We study here the combined problem of scheduling and power control, where we seek both an assignment of power ... Keywords: Wireless networks, capacity, radio interference, scheduling

Magnús M. Halldórsson

2012-12-01T23:59:59.000Z

29

Power optimized programmable embedded controller  

E-Print Network (OSTI)

Now a days, power has become a primary consideration in hardware design, and is critical in computer systems especially for portable devices with high performance and more functionality. Clock-gating is the most common technique used for reducing processor's power. In this work clock gating technique is applied to optimize the power of fully programmable Embedded Controller (PEC) employing RISC architecture. The CPU designed supports i) smart instruction set, ii) I/O port, UART iii) on-chip clocking to provide a range of frequencies , iv) RISC as well as controller concepts. The whole design is captured using VHDL and is implemented on FPGA chip using Xilinx .The architecture and clock gating technique together is found to reduce the power consumption by 33.33% of total power consumed by this chip.

Kamaraju, M; Tilak, A V N; 10.5121/ijcnc.2010.2409

2010-01-01T23:59:59.000Z

30

Lateral Al{sub x}Ga{sub 1-x}N power rectifiers with 9.7 kV reverse breakdown voltage  

SciTech Connect

Al{sub x}Ga{sub 1-x}N (x=0--0.25) Schottky rectifiers were fabricated in a lateral geometry employing p{sup +}-implanted guard rings and rectifying contact overlap onto an SiO{sub 2} passivation layer. The reverse breakdown voltage (V{sub B}) increased with the spacing between Schottky and ohmic metal contacts, reaching 9700 V for Al{sub 0.25}Ga{sub 0.75}N and 6350 V for GaN, respectively, for 100 {mu}m gap spacing. Assuming lateral depletion, these values correspond to breakdown field strengths of {<=}9.67x10{sup 5}Vcm{sup -1}, which is roughly a factor of 20 lower than the theoretical maximum in bulk GaN. The figure of merit (V{sub B}){sup 2}/R{sub ON}, where R{sub ON} is the on-state resistance, was in the range 94--268 MWcm-2 for all the devices.

Zhang, A. P.; Johnson, J. W.; Ren, F.; Han, J.; Polyakov, A. Y.; Smirnov, N. B.; Govorkov, A. V.; Redwing, J. M.; Lee, K. P.; Pearton, S. J.

2001-02-05T23:59:59.000Z

31

Power control for heat engines  

DOE Patents (OSTI)

A power control arrangement for a Stirling engine includes a sleeve mounted in each cylinder for axial movement and a port in the sleeve leading to a dead space. The port is covered by the piston at a position that is determined by the piston position and the axial adjustment of the sleeve. The compression phase of the Stirling cycle for that piston begins when the port is covered, so the position of the sleeve is used to set the Stirling engine power level.

Dineen, John J. (Durham, NH)

1984-01-01T23:59:59.000Z

32

Active Power Control from Wind Power (Presentation)  

DOE Green Energy (OSTI)

In order to keep the electricity grid stable and the lights on, the power system relies on certain responses from its generating fleet. This presentation evaluates the potential for wind turbines and wind power plants to provide these services and assist the grid during critical times.

Ela, E.; Brooks, D.

2011-04-01T23:59:59.000Z

33

Resonant Power Conditioning and Compact Pulse Power ...  

Science Conference Proceedings (OSTI)

... (FEEDBACK) HV RECTIFIER AND FILTER NETWORK ... Los Alamos High Frequency “Polyphase Resonant Power Conditioning” ... 30 KW Loss ...

2012-10-31T23:59:59.000Z

34

An efficient CMOS rectifier with low-voltage operation for RFID tags  

Science Conference Proceedings (OSTI)

A high-efficiency CMOS rectifier for radio-frequency identification (RFID) applications is presented. Using an on-chip generated clock signal, a new switching scheme is proposed to enhance the power efficiency of the conventional 4 transistor (4T)-cell ... Keywords: frequency 950 MHz, efficient CMOS rectifier, low-voltage operation, RFID tags, radio-frequency identification applications, on-chip generated clock signal, power efficiency, conventional 4 transistor-cell rectifier, charge-transfer transistors, small leakage current, external gate-boosting technique, nominal standard threshold voltage, MOS transistors, CMOS technology, power conversion efficiency

P. Kamalinejad; S. Mirabbasi; V. C. M. Leung

2011-07-01T23:59:59.000Z

35

Remote-Controllable Power Outlet System for Home Power Management  

Science Conference Proceedings (OSTI)

In this paper we describe the Wireless Power-Controlled Outlet Module (WPCOM) with a scalable mechanism for home power management which we have developed. The WPCOM integrates the multiple AC power sockets and a simple low-power microcontroller into ...

Chia-Hung Lien; Ying-Wen Bai; Ming-Bo Lin

2007-11-01T23:59:59.000Z

36

Control system for cogenerative power plants  

Science Conference Proceedings (OSTI)

The paper presents a distributed control system for the realization of cogenerative supply of electricity and heat and, in given case, for their combination with waste heat recovery, particularly in combined (gas-steam) cycle industrial power plants. ... Keywords: cogenerative gas power plant, control of distributed parameter systems, distribution management system, electric power systems, optimization, process control, real time systems, simulation

Florin Hartescu

2008-08-01T23:59:59.000Z

37

Power control system and method  

SciTech Connect

A power system includes an energy harvesting device, a battery coupled to the energy harvesting device, and a circuit coupled to the energy harvesting device and the battery. The circuit is adapted to deliver power to a load by providing power generated by the energy harvesting device to the load without delivering excess power to the battery and to supplement the power generated by the energy harvesting device with power from the battery if the power generated by the energy harvesting device is insufficient to fully power the load. A method of operating the power system is also provided.

Steigerwald, Robert Louis (Burnt Hills, NY); Anderson, Todd Alan (Niskayuna, NY)

2008-02-19T23:59:59.000Z

38

Flex power perspectives of indirect power system control through dynamic  

Open Energy Info (EERE)

Flex power perspectives of indirect power system control through dynamic Flex power perspectives of indirect power system control through dynamic power price (Smart Grid Project) Jump to: navigation, search Project Name Flex power perspectives of indirect power system control through dynamic power price Country Denmark Coordinates 56.26392°, 9.501785° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":56.26392,"lon":9.501785,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

39

NREL: Transmission Grid Integration - Active Power Controls  

NLE Websites -- All DOE Office Websites (Extended Search)

Active Power Controls Active Power Controls NREL has teamed with the Electric Power Research Institute, the Colorado School of Mines, the University of Colorado, and other industry members to research the potential of wind turbines and power plants to provide active power control (also known as real power or frequency control) to the electric power system. Under this multiyear project, researchers will perform simulations and field tests at the National Wind Technology Center to analyze system benefits and impacts on the operations of wind turbines and the electric power system. The project considers five topics: Steady state and economics Dynamic interconnection stability Controls design and simulation Controls testing and loads and structural impacts Dissemination of results.

40

Active Power and Nonactive Power Control of Distributed Energy Resources  

SciTech Connect

Distributed energy resources (DE) have been widely used in the power systems to supply active power, and most of the present DE resources are operated with limited or without nonactive power capability. This paper shows that with a slight modification in hardware configuration and a small boost in the power ratings, as well as proper implementation of control strategies, a DE system with a power electronics converter interface can provide active power and nonactive power simultaneously and independently. A DE can provide dynamic voltage regulation to the local bus because of its nonactive power capability. Furthermore, the proposed DE control method in this paper can effectively compensate the unbalance in the local voltage. The system requirements such as the inverter current rating and the dc voltage rating are discussed. The analysis of the system requirements to provide nonactive power shows that it is cost-effective to have DE provide voltage regulation.

Xu, Yan [ORNL; Li, Fangxing [ORNL; Rizy, D Tom [ORNL; Kueck, John D [ORNL

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Magnetically Controlled Reactor Shrinks Power Quality Costs and Power  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetically Controlled Reactor Shrinks Power Quality Costs and Power Magnetically Controlled Reactor Shrinks Power Quality Costs and Power Losses Speaker(s): Mark D. Galperin Date: December 18, 2000 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Diana Morris In a new, magnetically controlled reactor (MCR), in which DC pulsing through a special winding controls inductive susceptance, high saturation of the magnetic circuit steel with optimal magnetic and electrical circuit parameters ensures less than 2-3% main harmonic distortion even without special filters. Transformer-like construction ensures reliable operation. MCR's increase power quality through automatic voltage regulation, reduced fluctuation, and smoothing of reactive power surges at 1/2 the cost of thyristor-controlled reactors (TCR's). Damping of voltage-oscillation

42

Power Control in Wireless Cellular Networks  

Science Conference Proceedings (OSTI)

Transmit power in wireless cellular networks is a key degree of freedom in the management of interference, energy, and connectivity. Power control in both the uplink and downlink of a cellular network has been extensively studied, especially over the ...

Mung Chiang; Prashanth Hande; Tian Lan; Chee Wei Tan

2008-04-01T23:59:59.000Z

43

Advanced nonlinear control of complex power systems.  

E-Print Network (OSTI)

??Nowadays, advanced controller design is called upon to guarantee the secure and reliable operation of power systems. To meet this requirement, this work proposed three… (more)

Li, Hong Yin.

2008-01-01T23:59:59.000Z

44

Dynamic Reactive Power Control of Isolated Power Systems  

E-Print Network (OSTI)

This dissertation presents dynamic reactive power control of isolated power systems. Isolated systems include MicroGrids in islanded mode, shipboard power systems operating offshore, or any other power system operating in islanded mode intentionally or due to a fault. Isolated power systems experience fast transients due to lack of an infinite bus capable of dictating the voltage and frequency reference. This dissertation only focuses on reactive control of islanded MicroGrids and AC/DC shipboard power systems. The problem is tackled using a Model Predictive Control (MPC) method, which uses a simplified model of the system to predict the voltage behavior of the system in future. The MPC method minimizes the voltage deviation of the predicted bus voltage; therefore, it is inherently robust and stable. In other words, this method can easily predict the behavior of the system and take necessary control actions to avoid instability. Further, this method is capable of reaching a smooth voltage profile and rejecting possible disturbances in the system. The studied MicroGrids in this dissertation integrate intermittent distributed energy resources such as wind and solar generators. These non-dispatchable sources add to the uncertainty of the system and make voltage and reactive control more challenging. The model predictive controller uses the capability of these sources and coordinates them dynamically to achieve the voltage goals of the controller. The MPC controller is implemented online in a closed control loop, which means it is self-correcting with the feedback it receives from the system.

Falahi, Milad

2012-12-01T23:59:59.000Z

45

Automatic control in electric power systems  

Science Conference Proceedings (OSTI)

The recent progress in the application of automatic controls to electric power systems is outlined. After a brief review of present trends in power system planning and operation, the role of computers and of modern control methods and techniques in optimal ...

G. Quazza

1970-01-01T23:59:59.000Z

46

Advanced Power Electronics Controllers for Substations  

Science Conference Proceedings (OSTI)

Substations located at various points in the power delivery system serve several purposes. In a broad sense, power substations are installations capable of interrupting or establishing electric circuits and changing the voltage level, frequency, or other characteristic of the electric energy flow. Solid-state power electronic switching devices are continuing to evolve and multi-megawatt solid-state power control systems are becoming increasingly applied in industrial electrical installations. Both have a...

2008-12-17T23:59:59.000Z

47

Wind Power Plant SCADA and Controls  

SciTech Connect

Modern Wind Power Plants (WPPs) contain a variety of intelligent electronic devices (IEDs), Supervisory Control and Data Acquisition (SCADA) and communication systems. This paper discusses the issues related to a typical WPP's SCADA and Control. Presentation topics are: (1) Wind Turbine Controls; (2) Wind Plant SCADA, OEM SCADA Solutions, Third-Party SCADA Solutions; (3) Wind Plant Control; and (4) Security and Reliability Compliance.

Badrzadeh, Babak [IEEE PES Wind Plant Collector System Design Working Group; Castillo, Nestor [IEEE PES Wind Plant Collector System Design Working Group; Bradt, M. [IEEE PES Wind Plant Collector System Design Working Group; Janakiraman, R. [IEEE PES Wind Plant Collector System Design Working Group; Kennedy, R. [IEEE PES Wind Plant Collector System Design Working Group; Klein, S. [IEEE PES Wind Plant Collector System Design Working Group; Smith, Travis M [ORNL; Vargas, L. [IEEE PES Wind Plant Collector System Design Working Group

2011-01-01T23:59:59.000Z

48

Power management and power control in wireless networks  

E-Print Network (OSTI)

With the proliferation of portable computing platforms and small wireless devices, wireless networks have received more and more attention as a means for providing data communications among devices regardless of their physical locations. However, due to the slow advancement in battery technology, battery power continues to be a constrained resource in wireless networks and thus energy conservation remains to be an important issue. In this book chapter, we provide a taxonomy of power management and power control algorithms and protocols for wireless networks. We start with a description of energy consumption characteristics of wireless devices, and identify the power consumed in the wireless transmitters essentially consists of two parts: power consumed by the radio electronic and power consumed in the RF output. To save power, one can either turn off the radio electronic and put wireless devices into the power saving mode at appropriate times, or adjust the RF output power (and hence the wireless transmission range) subject to maintaining network connectivity and bi-directionality. The former techniques are termed as power management, while the latter power

Rong Zheng; Jennifer C. Hou; Ning Li

2004-01-01T23:59:59.000Z

49

Recovery Act: High-Efficiency, Wideband Three-Phase Rectifiers and Adaptive Rectifier Management for Telecomm Central Office and Large Data Center Applications  

Science Conference Proceedings (OSTI)

Lineage Power and Verizon teamed up to address a DOE funding opportunity focused on improving the power conversion chain in telecommunications facilities and data centers. The project had three significant elements: the design and development of high efficiency and high power three-phase rectifiers by Lineage Power, design and development of software to optimize overall plant energy efficiency by Lineage Power, and a field trial in active Verizon telecommunications facilities where energy consumption was measured before and after efficiency upgrades.

Mark A. Johnson

2012-06-29T23:59:59.000Z

50

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

amount of wind power generation that can be accommodated.ramping of generation Power and Frequency Control as itfrequency to loss of generation Power and Frequency Control

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

51

Quality control during construction of power plants  

SciTech Connect

This paper traces the background and examines the necessity for a program to control quality during the construction phase of a power plant. It also attempts to point out considerations for making these programs cost effective.

Hartstern, R.F.

1982-03-01T23:59:59.000Z

52

Variable pressure power cycle and control system  

DOE Patents (OSTI)

A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.

Goldsberry, Fred L. (Spring, TX)

1984-11-27T23:59:59.000Z

53

Interphase power controller with voltage injection  

Science Conference Proceedings (OSTI)

This paper introduces a new family of Interphase Power Controllers (IPC) based on the principle of voltage injection commonly used in phase-shifting transformers (PST). The voltage injection IPC exhibits power (active and reactive) control characteristics similar to previously defined IPC's and retains their inherent qualities: passive control, short circuit limitation and voltage decoupling. It also provides more flexibility for the adjustment of the operating points. Two promising topologies are described in more detail. One of them offers the potential of retrofitting existing phase-shifting transformers into full-fledged IPC's.

Beauregard, F.; Brochu, J.; Morin, G.; Pelletier, P. (Centre d'Innovation sur le Transport d'Energie du Quebec, Varennes, Quebec (Canada))

1994-10-01T23:59:59.000Z

54

Magnetic Amplifier for Power Flow Control  

Science Conference Proceedings (OSTI)

GENI Project: ORNL is developing an electromagnet-based, amplifier-like device that will allow for complete control over the flow of power within the electric grid. To date, complete control of power flow within the grid has been prohibitively expensive. ORNL’s controller could provide a reliable, cost-effective solution to this problem. The team is combining two types of pre-existing technologies to assist in flow control, culminating in a prototype iron-based magnetic amplifier. Ordinarily, such a device would require expensive superconductive wire, but the magnetic iron core of ORNL’s device could serve as a low-cost alternative that is equally adept at regulating power flow.

None

2012-02-24T23:59:59.000Z

55

INTEGRATED CONTROL OF NEXT GENERATION POWER SYSTEM  

Science Conference Proceedings (OSTI)

Control methodologies provide the necessary data acquisition, analysis and corrective actions needed to maintain the state of an electric power system within acceptable operating limits. These methods are primarily software-based algorithms that are nonfunctional unless properly integrated with system data and the appropriate control devices. Components of the control of power systems today include protective relays, supervisory control and data acquisition (SCADA), distribution automation (DA), feeder automation, software agents, sensors, control devices and communications. Necessary corrective actions are still accomplished using large electromechanical devices such as vacuum, oil and gas-insulated breakers, capacitor banks, regulators, transformer tap changers, reclosers, generators, and more recently FACTS (flexible AC transmission system) devices. The recent evolution of multi-agent system (MAS) technologies has been reviewed and effort made to integrate MAS into next generation power systems. A MAS can be defined as ��a loosely-coupled network of problem solvers that work together to solve problems that are beyond their individual capabilities��. These problem solvers, often called agents, are autonomous and may be heterogeneous in nature. This project has shown that a MAS has significant advantages over a single, monolithic, centralized problem solver for next generation power systems. Various communication media are being used in the electric power system today, including copper, optical fiber and power line carrier (PLC) as well as wireless technologies. These technologies have enabled the deployment of substation automation (SA) at many facilities. Recently, carrier and wireless technologies have been developed and demonstrated on a pilot basis. Hence, efforts have been made by this project to penetrate these communication technologies as an infrastructure for next generation power systems. This project has thus pursued efforts to use specific MAS methods as well as pertinent communications protocols to imbed and assess such technologies in a real electric power distribution system, specifically the Circuit of the Future (CoF) developed by Southern California Edison (SCE). By modeling the behavior and communication for the components of a MAS, the operation and control of the power distribution circuit have been enhanced. The use of MAS to model and integrate a power distribution circuit offers a significantly different approach to the design of next generation power systems. For example, ways to control a power distribution circuit that includes a micro-grid while considering the impacts of thermal constraints, and integrating voltage control and renewable energy sources on the main power system have been pursued. Both computer simulations and laboratory testbeds have been used to demonstrate such technologies in electric power distribution systems. An economic assessment of MAS in electric power systems was also performed during this project. A report on the economic feasibility of MAS for electric power systems was prepared, and particularly discusses the feasibility of incorporating MAS in transmission and distribution (T&D) systems. Also, the commercial viability of deploying MAS in T&D systems has been assessed by developing an initial case study using utility input to estimate the benefits of deploying MAS. In summary, the MAS approach, which had previously been investigated with good success by APERC for naval shipboard applications, has now been applied with promising results for enhancing an electric power distribution circuit, such as the Circuit of the Future developed by Southern California Edison. The results for next generation power systems include better ability to reconfigure circuits, improve protection and enhance reliability.

None

2010-02-28T23:59:59.000Z

56

HVDC Control Strategies to Improve Transient Stability in Interconnected Power Systems  

E-Print Network (OSTI)

PHEV's Park as a Virtual Active Filter for HVDC Networks F. R. Islam, H. R. Pota and A. B. M.Nasiruzzaman@student.adfa.edu.au Abstract--The HVDC converters used for rectifying or in- verting operations absorb reactive power from produces harmonics in both sides of HVDC links. Passive and active filters are used to filter the harmonics

Paris-Sud XI, Université de

57

Control system for wind-powered generators  

DOE Green Energy (OSTI)

In a system of wind-powered generators, a reliable yet inexpensive control system is desirable. Such a system would be completely automatic so it could be left unattended for long periods. It would respond to electrical representations of data such as bearing temperature, vibration, wind velocity, turbine velocity, torque, or any other pertinent data. It would respond by starting or stopping the turbine, controlling the loading, or sounding an alarm. A microprocessor-based controller capable of these functions is described.

Kroth, G.J.

1977-05-01T23:59:59.000Z

58

A noise rejection deadbeat control technique for active power filter  

Science Conference Proceedings (OSTI)

Compared with power filter, active power filter has a lot of advantages and it is an efficient technique to eliminate or limit the harmonic pollution in power system. However, the control of active power filter is very complex, and the control of current ... Keywords: active power filter, current control technique, deadbeat control, noise rejection, periodic noise, resetting integrator, sampling noise

Li-Dan Zhou; Mansoor Mansoor; Qian Ai; Da Xie; Chen Chen

2005-10-01T23:59:59.000Z

59

Preventing, Controlling and Mitigating Power System Separation  

Science Conference Proceedings (OSTI)

Large power system blackouts, although infrequent, may affect up to tens of millions of people and result in huge costs. A blackout is the result of a sequence of disturbances including initial events, consequent protective actions or additional failures, related vulnerability conditions, and accelerated cascading outages leading to the final blackout. Those disturbances may gradually weaken a power system's connections and result in growing angular oscillations between inter-connected control areas. If ...

2010-12-01T23:59:59.000Z

60

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

2   1.4   Modes of Power Plant32   4.3   Power Plant Controls (Plant Operation by24. Effect of frequency bias in power plant preselected load

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Study the power flow control of a power system with unified power flow controller.  

E-Print Network (OSTI)

??Electrical power systems is a large interconnected network that requires a careful design to maintain the system with continuous power flow operation without any limitations.… (more)

Peesari, Vakula

2010-01-01T23:59:59.000Z

62

Nuclear Power - Control, Reliability and Human Factors  

E-Print Network (OSTI)

Advances in reactor designs, materials and human-machine interfaces guarantee safety and reliability of emerging reactor technologies, eliminating possibilities for high-consequence human errors as those which have occurred in the past. New instrumentation and control technologies based in digital systems, novel sensors and measurement approaches facilitate safety, reliability and economic competitiveness of nuclear power options. Autonomous operation scenarios are becoming increasingly popular to consider for small modular systems. This book belongs to a series of books on nuclear power published by InTech. It consists of four major sections and contains twenty-one chapters on topics from key subject areas pertinent to instrumentation and control, operation reliability, system aging and human-machine interfaces. The book targets a broad potential readership group - students, researchers and specialists in the field - who are interested in learning about nuclear power.

Tsvetkov, Pavel

2011-09-01T23:59:59.000Z

63

Power Flow Controller for Renewables: Transformer-less Unified Power Flow Controller for Wind and Solar Power Transmission  

SciTech Connect

GENI Project: MSU is developing a power flow controller to improve the routing of electricity from renewable sources through existing power lines. The fast, innovative, and lightweight circuitry that MSU is incorporating into its controller will eliminate the need for a separate heavy and expensive transformer, as well as the construction of new transmission lines. MSU’s controller is better suited to control power flows from distributed and intermittent wind and solar power systems than traditional transformer-based controllers are, so it will help to integrate more renewable energy into the grid. MSU‘s power flow controller can be installed anywhere in the existing grid to optimize energy transmission and help reduce transmission congestion.

None

2012-02-08T23:59:59.000Z

64

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

inherent in power system operations. Primary Control is theoperation of a power system is described in terms of primary and secondary control

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

65

Power reduction control for inductive lighting installation  

SciTech Connect

A control system for continuously, selectively reducing power consumption in an inductive lighting installation energized from an A.C. power source, the installation including at least one gas discharge lamp such as a fluorescent lamp energized through any of a plurality of different types of electromagnetic ballast having different harmonic distortion characteristics, the control system is described comprising: load energizing circuit means, including a signal-actuated normally-closed primary switch, for connecting an A.C. power source to the lighting installation; a signal-actuated, normally-open secondary switch connected in parallel with the lighting installation; actuation means for generating actuation signals and applying such actuation signals to the primary and secondary switches to actuate the primary switch open and to actuate the secondary switch closed in approximate time coincidence in each half-cycle of the A.C. power; zero-crossing detector means for generating zero-crossing signals at times TX indicative of zero-voltage transitions in the A.C. power; and program means, connected to the zero-crossing detector means and to the actuation means, programming the actuation means to generate (a) power reduction actuation signals at times T1 and T2 in each half-cycle of the A.C. power, (b) a first filter actuation signal at a time T3 prior to each zero-crossing time TX, and (c) a second filter actuation signal at a time T4 following each zero-crossing time TX; the program means including a plurality of programs each establishing a set of times T1, T2, T3 and T4 for several different power reduction levels for a particular type of ballast; and selection means for selecting a program to match the ballast type of the load.

Falk, K.R.

1993-06-22T23:59:59.000Z

66

Modeling of Electronically Commutated Motor Controlled Fan-powered Terminal Units  

E-Print Network (OSTI)

Empirical models of airflow and power consumption were developed for series and parallel variable air volume fan powered terminal units (FPTUs). An experimental setup and test procedure were developed to test the terminal units over typical operating ranges. The terminal units in this study used either an 8 in. (20.32 cm) or a 12 in. (30.48 cm) primary air inlet. All terminal units utilized electronically commutated motor (ECM) controllers. Data collected were compared against previous data collected for silicon controlled rectifier (SCR) units. Generalized models were developed for both series and parallel units, and compared against models developed for SCR units. In addition to the performance modeling, power factor and power quality data were also collected for each terminal unit. The power quality analysis included recording and analyzing harmonic distortion for current, voltage, and power up to the 25th harmonic. The total harmonic distortion (THD) was also recorded and presented. For the series terminal units, models were developed for fan airflow, fan power, and primary airflow. The models for fan airflow all had R2 values above 0.987. The models for fan power all had R2 values above 0.968. The models for primary airflow all had R2 values above 0.895. For the parallel terminal units, models were developed for leakage, fan airflow, fan power, and primary airflow. All of the leakage models had R2 values above 0.826. All of the fan airflow models had R2 values above 0.955. All of the fan power models had R2 values above 0.922. All of the primary airflow models had R2 values above 0.872. The real power THD was below 1.5 percent for both series and parallel FPTUs. The current THD ranged from 84 percent to 172 percent for series FPTUs and from 83 percent to 183 percent for parallel FPTUs. The voltage THD was below 1.4 percent for both series and parallel FPTUs. The performance models developed will help improve the accuracy of building energy simulation programs for heating, ventilation, and air conditioning (HVAC) systems utilizing ECM controlled FPTUs. Increasing the accuracy of these simulations will allow HVAC system designers to better optimize their designs for specific building types in a wide variety of climates.

Edmondson, Jacob Lee

2009-12-01T23:59:59.000Z

67

VAR control: leading and lagging power factor  

SciTech Connect

Using the examples of power system failures in Jacksonville, Florida, New York City, and France which were the result of either a deficiency of installed VAR generation sources or an excess of VAR's after the affected system had been isolated, the problem of VAR control in general is discussed and some insight is provided as to how situations can occur to cause system instability because of deficient or excess VARS. (LCL)

Boyle, J.R.

1980-01-01T23:59:59.000Z

68

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2006-03-14T23:59:59.000Z

69

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2008-03-25T23:59:59.000Z

70

Assessment of Retro-Fit Energy Savings Devices: Power-R-Command 3000  

Science Conference Proceedings (OSTI)

This report describes and documents the energy savings and efficiency, limited power quality, and photometric performance of Eaton Power's Power-R-Command 3000 (PRC 3000) Lighting Controller. This unit contains three individual silicon-control rectifier-based (SCR-based) load management systems. These power electronics-based systems, which can either be bypassed or activated to provide a predetermined amount of energy savings, are controlled by computer through an Eaton interconnect via Eaton programmabl...

2010-07-30T23:59:59.000Z

71

Enforcement Letter, Controlled Power Company - WEL-2012-02 |...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Power Company - WEL-2012-02 October 23, 2012 Enforcement Letter issued to Controlled Power Company related to an Electrical Shock Near Miss that occurred in the Radiological...

72

Controlling hour-long power of wind farms.  

E-Print Network (OSTI)

??In attempting to control the power output of a wind farm, it is first necessary to smooth the power fluctuations due to wind turbulence. This… (more)

Li, Pei, 1981-

2007-01-01T23:59:59.000Z

73

MODULAR CONTROL OF FUSION POWER HEATING APPLICATIONS  

SciTech Connect

This work is motivated by the growing demand for auxiliary heating on small and large machines worldwide. Numerous present and planned RF experiments (EBW, Lower Hybrid, ICRF, and ECH) are increasingly complex systems. The operational challenges are indicative of a need for components of real-time control that can be implemented with a moderate amount of effort in a time- and cost-effective fashion. Such a system will improve experimental efficiency, enhance experimental quality, and expedite technological advancements. The modular architecture of this control-suite serves multiple purposes. It facilitates construction on various scales from single to multiple controller systems. It enables expandability of control from basic to complex via the addition of modules with varying functionalities. It simplifies the control implementation process by reducing layers of software and electronic development. While conceived with fusion applications in mind, this suite has the potential to serve a broad range of scientific and industrial applications. During the Phase-I research effort we established the overall feasibility of this modular control-suite concept. We developed the fundamental modules needed to implement open-loop active-control and demonstrated their use on a microwave power deposition experiment.

D.R.Demers

2012-08-24T23:59:59.000Z

74

Digitally Controlled High Availability Power Supply  

SciTech Connect

This paper reports the design and test results on novel topology, high-efficiency, and low operating temperature, 1,320-watt power modules for high availability power supplies. The modules permit parallel operation for N+1 redundancy with hot swap capability. An embedded DSP provides intelligent start-up and shutdown, output regulation, general control and fault detection. PWM modules in the DSP drive the FET switches at 20 to 100 kHz. The DSP also ensures current sharing between modules, synchronized switching, and soft start up for hot swapping. The module voltage and current have dedicated ADCs (>200 kS/sec) to provide pulse-by-pulse output control. A Dual CAN bus interface provides for low cost redundant control paths. Over-rated module components provide high reliability and high efficiency at full load. Low on-resistance FETs replace conventional diodes in the buck regulator. Saturable inductors limit the FET reverse diode current during switching. The modules operate in a two-quadrant mode, allowing bipolar output from complimentary module groups. Controllable, low resistance FETs at the input and output provide fault isolation and allow module hot swapping.

MacNair, David; /SLAC

2008-09-25T23:59:59.000Z

75

Energy conversion apparatus for supplying variable voltage direct current power to an electrically propelled vehicle  

SciTech Connect

A synchronous machine, operable as both a motor and a generator, is mounted on an electrically powered vehicle, such as a mine shuttle car, and includes a plurality of conductors having connections that are detachably engagable with receptacles of a stationary power bank. Engagement of the conductors with the receptacles supplies variable voltage alternating current power to the machine. The machine is drivingly connected to a flywheel on the vehicle and, operating as a motor, energizes the flywheel to store a preselected amount of mechanical energy. The electrical connection between the vehicle and the power bank is opened after the flywheel has been sufficiently charged. The stored energy in the flywheel is then available to drive the machine as a generator and produce high frequency, three phase, alternating current power. The generated power is transmitted to a full wave silicon controlled rectifier that converts the alternating current power to direct current for powering the traction motors of the vehicle. A variable voltage controller is connected to the rectifier and actuates the rectifier to supply direct current at a selected voltage level. The controller is responsive to an operator foot pedal. By manually depressing the foot pedal to a selected position, the voltage level of the rectified current is controlled. Thus, the speed of the traction motors is adjustable topropel the vehicle at a speed within a given range. After a portion of the energy stored by the flywheel is consumed, the vehicle is returned to the power bank to replenish the energy supply.

Jamison, W.B.; Burr, J.F.

1976-09-07T23:59:59.000Z

76

Experience curves for power plant emission control technologies  

E-Print Network (OSTI)

1/2, 2004 Experience curves for power plant emission controlcoal-fired electric power plants. In particular, we focus on2004) ‘Experience curves for power plant emission control

Rubin, Edward S.; Yeh, Sonia; Hounshell, David A; Taylor, Margaret R

2007-01-01T23:59:59.000Z

77

State-of-the-Art Electrostatic Precipitator Power Supplies  

Science Conference Proceedings (OSTI)

New electrostatic precipitator (ESP) power supply controls are available that can significantly enhance the performance of precipitators. These controls are capable of intermittent energization and bad corona detection, as well as ESP data archiving and performance troubleshooting. Furthermore, a new generation of power supplies for electrostatic precipitators is now on the market. These new high frequency supplies are smaller and lighter than the 60 hertz transformer – rectifier power supplies the...

2003-10-28T23:59:59.000Z

78

On power quality control center for providing unbundled power quality services.  

E-Print Network (OSTI)

??Using Power Quality Control Center (PQCC) to provide unbundled power quality services is investigated in this thesis. It begins with a detailed analysis of the… (more)

Zhan, Yanqin.

2008-01-01T23:59:59.000Z

79

Wind energy and power system interconnection, control, and operation for high penetration of wind power .  

E-Print Network (OSTI)

??High penetration of wind energy requires innovations in different areas of power engineering. Methods for improving wind energy and power system interconnection, control, and operation… (more)

Liang, Jiaqi

2012-01-01T23:59:59.000Z

80

Auxiliary power controls on the Nelson River HVDC scheme  

SciTech Connect

This paper describes the auxiliary power controls on the Nelson River HVDC scheme. It shows how the fast control feature of the HVDC link can be utilized to enhance the operation of an integrated ac/dc power system.

Chand, J. (Manitoba Hydro, Winnipeg, Manitoba (CA))

1992-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Experience curves for power plant emission control technologies  

E-Print Network (OSTI)

power plant emission control technologies Historical growthpower plant emission control technologies The environmental policy initiatives responsible for the substantial growthfired power plants. E.S. Rubin et al. Historical growth in

Rubin, Edward S.; Yeh, Sonia; Hounshell, David A

2007-01-01T23:59:59.000Z

82

BATTERY STORAGE CONTROL FOR STEADYING RENEWABLE POWER GENERATION  

E-Print Network (OSTI)

BATTERY STORAGE CONTROL FOR STEADYING RENEWABLE POWER GENERATION By Shengyuan (Mike) Chen, Emilie-626-7370 URL: http://www.ima.umn.edu #12;Battery Storage Control for Steadying Renewable Power Generation by storing excess power to a battery during excess generation, and then releasing the energy when power

83

Distributed Power Flow Control: Distributed Power Flow Control using Smart Wires for Energy Routing  

Science Conference Proceedings (OSTI)

GENI Project: Smart Wire Grid is developing a solution for controlling power flow within the electric grid to better manage unused and overall transmission capacity. The 300,000 miles of high-voltage transmission line in the U.S. today are congested and inefficient, with only around 50% of all transmission capacity utilized at any given time. Increased consumer demand should be met in part with more efficient and an economical power flow. Smart Wire Grid’s devices clamp onto existing transmission lines and control the flow of power within—much like how internet routers help allocate bandwidth throughout the web. Smart wires could support greater use of renewable energy by providing more consistent control over how that energy is routed within the grid on a real-time basis. This would lessen the concerns surrounding the grid’s inability to effectively store intermittent energy from renewables for later use.

None

2012-04-24T23:59:59.000Z

84

Digitally Controlled High Availability Power Supply  

SciTech Connect

This paper will report on the test results of a prototype 1320 watt power module for a high availability power supply. The module will allow parallel operation for N+1 redundancy with hot swap capability. The two quadrant output of each module allows pairs of modules to provide a 4 quadrant (bipolar) operation. Each module employs a novel 4 FET buck regulator arranged in a bridge configuration. Each side of the bridge alternately conducts through a small saturable ferrite that limits the reverse current in the FET body diode during turn off. This allows hard switching of the FETs with low switching losses. The module is designed with over-rated components to provide high reliability and better then 97% efficiency at full load. The modules use a Microchip DSP for control, monitoring, and fault detection. The switching FETS are driven by PWM modules in the DSP at 60 KHz. A Dual CAN bus interface provides for low cost redundant control paths. The DSP will also provide current sharing between modules, synchronized switching, and soft start up for hot swapping. The input and output of each module have low resistance FETs to allow hot swapping and isolation of faulted units.

MacNair, David; /SLAC

2009-05-07T23:59:59.000Z

85

Tuning three-term controllers for power station processes  

Science Conference Proceedings (OSTI)

This paper presents a new approach for tuning three-term control loops encountered in power station processes. The proposed approach is based on the Pseudo-Derivative Feedback (PDF) control configuration. Simple methods are presented for tuning the PDF ... Keywords: controller tuning, dead-time processes, power plant control, process control

K. G. Arvanitis; G. D. Pasgianos; A. K. Boglou

2006-07-01T23:59:59.000Z

86

Fuzzy gain scheduling technique for power flow control  

Science Conference Proceedings (OSTI)

An application of fuzzy logic based control for power systems governing multiple Flexible Alternating Current Transmission System (FACTS) devices is described here. Sufficiently accurate relations have been derived to determine setpoints of FACTS ... Keywords: AC transmission, FACTS devices, Switzerland, flexible alternating current transmission system, fuzzy control, fuzzy gain scheduling, fuzzy logic, power flow control, power systems, sensitivity analysis

Alexandre Oudalov; Petr Korba; Rachid Cherkaoui; Alain J. Germond

2006-10-01T23:59:59.000Z

87

Analysis of Control Interactions on FACTS-Assisted Power Systems  

Science Conference Proceedings (OSTI)

This report presents results of comprehensive analyses of the dynamic behavior for power systems controlled by multiple Flexible AC Transmission System (FACTS) Controllers. Using a representative "benchmark" power system throughout the analyses and studies, an approach identifying the most effective FACTS Controllers, location, type, and ratings was developed. The control and coordination among the implemented FACTS Controllers in the studied power system were extensively investigated.

1998-02-24T23:59:59.000Z

88

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

LFC) commands issued by BAs. In this regard they are verya power system in which two BAs are interconnected by aControl Error (ACE) of the BAs. Power and Frequency Control

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

89

Design of decentralized multivariable excitation controllers in multimachine power systems by projective controls  

Science Conference Proceedings (OSTI)

A methodology for the design of decentralized multivariable excitation and controllers in multimachine power systems is developed using projective controls. The existing methodology, is extended to permit the coordinated design of AVR and PSS controllers in power systems.

Arnautovic, D.; Medanic, J.

1987-12-01T23:59:59.000Z

90

Multivariable model predictive control for a gas turbine power plant  

Science Conference Proceedings (OSTI)

In this brief, constrained multi variable model predictive control (MPC) strategy is investigated for a GE9001E gas turbine power plant. So the rotor speed and exhaust gas temperature are controlled manipulating the fuel command and compressor inlet ... Keywords: ARX, gas turbine, identification, modeling, multivariable control, power plant, predictive control

Hadi Ghorbani; Ali Ghaffari; Mehdi Rahnama

2008-05-01T23:59:59.000Z

91

Brief paper: A power system nonlinear adaptive decentralized controller design  

Science Conference Proceedings (OSTI)

In this paper, a novel excitation control is designed for improvement of transient stability of power systems. The control algorithm is based on the adaptive backstepping method in a recursive way without linearizing the system model. Lyapunov function ... Keywords: Adaptive control, Backstepping design, Nonlinear decentralized control, Power systems, Transient stability

Rui Yan; ZhaoYang Dong; T. K. Saha; Rajat Majumder

2010-02-01T23:59:59.000Z

92

System of control in an offshore wind farm with HVdc link  

Science Conference Proceedings (OSTI)

This paper describes the coordination in control systems between the doubly fed induction generator (DFIG) and the firing delay angle control of the rectifier that comprises the HVdc transmission system based on a Line-Commutated Converter; as well as ... Keywords: HVdc transmission, control system, doubly fed induction generator, wind power generation

Miguel Montilla-Djesus; Santiago Arnaltes; David Santos Martin

2010-12-01T23:59:59.000Z

93

Distributed Battery Control for Peak Power Shaving in Datacenters  

E-Print Network (OSTI)

Distributed Battery Control for Peak Power Shaving in Datacenters Baris Aksanli and Tajana Rosing to shave peak power demands. Our novel distributed battery control design has no performance impact, reduces the peak power needs, and accurately estimates and maximizes the battery lifetime. We demonstrate

Simunic, Tajana

94

Ris-R-1118(EN) Power Control for Wind Tur-  

E-Print Network (OSTI)

storage or with an AC/DC converter and battery storage. The AC/DC converter can either be an "add-on" type installations, the cost of the power control is paid back as added wind power capacity value and saved grid reinforcement costs. Different systems for controlling the power output from a wind farm connected to a weak

95

Modern Control System Design for Hydro-power Plant.  

E-Print Network (OSTI)

??This thesis addresses dynamic model and advance controller design for entire Hydro-power plant. Although hydro-power has the best payback ratio and the highest efficiency in… (more)

Ding, Xibei

2011-01-01T23:59:59.000Z

96

Green Scheduling: Scheduling of Control Systems for Peak Power Reduction  

E-Print Network (OSTI)

approaches for load shifting and model predictive control have been proposed, we present an alternative approach to reduce the peak power for a set of control systems. The proposed model is intuitive, scalableGreen Scheduling: Scheduling of Control Systems for Peak Power Reduction Truong Nghiem, Madhur Behl

Pappas, George J.

97

Power and Voltage Smooth Control of Doubly Fed Induction Generator  

Science Conference Proceedings (OSTI)

Doubly-fed induction generator (DFIG) is the leading in wind power technology currently. In this paper, decoupling control of DFIG is studied and a new energy storage device is used in the smooth control of DFIG system's power and voltage. This new method ... Keywords: Doubly fed induction generator, Energy storage device, Decoupling control

An-Ren Ma, Cai-Xia Wang, Zhi-Wen Zhou, Tao Wu

2012-07-01T23:59:59.000Z

98

High Voltage GaN Schottky Rectifiers  

SciTech Connect

Mesa and planar GaN Schottky diode rectifiers with reverse breakdown voltages (V{sub RB}) up to 550V and >2000V, respectively, have been fabricated. The on-state resistance, R{sub ON}, was 6m{Omega}{center_dot} cm{sup 2} and 0.8{Omega}cm{sup 2}, respectively, producing figure-of-merit values for (V{sub RB}){sup 2}/R{sub ON} in the range 5-48 MW{center_dot}cm{sup -2}. At low biases the reverse leakage current was proportional to the size of the rectifying contact perimeter, while at high biases the current was proportional to the area of this contact. These results suggest that at low reverse biases, the leakage is dominated by the surface component, while at higher biases the bulk component dominates. On-state voltages were 3.5V for the 550V diodes and {ge}15 for the 2kV diodes. Reverse recovery times were <0.2{micro}sec for devices switched from a forward current density of {approx}500A{center_dot}cm{sup -2} to a reverse bias of 100V.

CAO,X.A.; CHO,H.; CHU,S.N.G.; CHUO,C.-C.; CHYI,J.-I.; DANG,G.T.; HAN,JUNG; LEE,C.-M.; PEARTON,S.J.; REN,F.; WILSON,R.G.; ZHANG,A.P.

1999-10-25T23:59:59.000Z

99

Protection and Control for Grid Connected Photovoltaic Power Generation System Based on Instantaneous Power Theory  

Science Conference Proceedings (OSTI)

Reliable protection and reasonable control run an important role in grid connected PV power generation system. The detection and calculation of real and reactive power are the bases of many inverter resident passive and active islanding detection method ... Keywords: Distributed generation, photovoltaic system, grid connected, protection and control, power theory

Fei Wang; Chengcheng Zhang

2009-05-01T23:59:59.000Z

100

Research on Control System of High Power DFIG Wind Power System  

Science Conference Proceedings (OSTI)

Compared with constant speed constant frequency wind turbine, variable speed constant frequency wind turbine has many advantages: higher efficiency of wind energy converting to electric power, absorbing gust energy, smoothly cutting into the network ... Keywords: wind power, DFIG, high power, LQR, variable speed constant frequency, constant power control

Li Jianlin; Xu Honghua

2008-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

MANAGING MODERNIZATION OF NUCLEAR POWER PLANT INSTRUMENTATION AND CONTROL SYSTEMS  

E-Print Network (OSTI)

Managing modernization of nuclear power plant instrumentation and control systems February 2004The originating Section of this publication in the IAEA was:

unknown authors

2003-01-01T23:59:59.000Z

102

Reinforcement learning techniques for controlling resources in power networks.  

E-Print Network (OSTI)

??As power grids transition towards increased reliance on renewable generation, energy storage and demand response resources, an effective control architecture is required to harness the… (more)

Kowli, Anupama

2013-01-01T23:59:59.000Z

103

Dynamic Power Flow Controller: Compact Dynamic Phase Angle Regulators for Transmission Power Routing  

SciTech Connect

GENI Project: Varentec is developing compact, low-cost transmission power controllers with fractional power rating for controlling power flow on transmission networks. The technology will enhance grid operations through improved use of current assets and by dramatically reducing the number of transmission lines that have to be built to meet increasing contributions of renewable energy sources like wind and solar. The proposed transmission controllers would allow for the dynamic control of voltage and power flow, improving the grid’s ability to dispatch power in real time to the places where it is most needed. The controllers would work as fail-safe devices whereby the grid would be restored to its present operating state in the event of a controller malfunction instead of failing outright. The ability to affordably and dynamically control power flow with adequate fail-safe switchgear could open up new competitive energy markets which are not possible under the current regulatory structure and technology base.

None

2012-01-03T23:59:59.000Z

104

Molecular rectifying diodes from self-assembly on silicon  

E-Print Network (OSTI)

Molecular rectifying diodes from self-assembly on silicon Stéphane Lenfant , Christophe Krzeminski a molecular rectifying junction made from a sequential self-assembly on silicon. The device structure consists resonance through the highest occupied molecular orbital of the -group in good agreement with our

Paris-Sud XI, Université de

105

Power System Backup Control Center Requirements  

Science Conference Proceedings (OSTI)

The North American Electric Reliability Council (NERC) requested a reference document to aid control center managers in scoping, justifying, and planning backup control centers. This report serves as a guide for cost-effective implementation of a backup control center.

1994-04-01T23:59:59.000Z

106

Advanced Power Systems and Controls Laboratory  

E-Print Network (OSTI)

. Conclusions As utility scale PV and rooftop solar PV become commonplace on our electric grid, battery energy Solar Power Generation Introduction The rapid growth of wind and solar power is a key driver of the development of grid-scale Battery Energy Storage Systems (BESS). A well implemented BESS co-located with solar

107

Application of the interphase power controller technology for transmission line power flow control  

SciTech Connect

This paper presents an application of the IPC technology for controlling power flows while maintaining the natural synchronizing capacity of transmission lines. The benefits for transmission systems are a substantial increase in steady-state transmission capability, lower losses and voltage support. An example based on the 500 kV Mead-Phoenix Project demonstrates the effectiveness of the IPC solution: the addition of a 370 Mvar capacitor in parallel with the two 500 kV phase-shifting transformers increases their maximum capability from 1,300 to 1,910 MW. The concepts presented are the results of the first phase of work leading to the development of an IPC using power electronics.

Brochu, J.; Beauregard, F.; Lemay, J.; Morin, G.; Pelletier, P. [Center d`Innovation sur le Transport d`Energie du Quebec, Varennes, Quebec (Canada)] [Center d`Innovation sur le Transport d`Energie du Quebec, Varennes, Quebec (Canada); Thallam, R.S. [Salt River Project, Phoenix, AZ (United States)] [Salt River Project, Phoenix, AZ (United States)

1997-04-01T23:59:59.000Z

108

The making of multimedia power systems control and simulation labware  

Science Conference Proceedings (OSTI)

This paper discusses the development of a multimedia, PC-based, hydro-electric power generation system simulator to interface, via real-time data acquisition and control, to programmable logic controllers. The project is ongoing. The paper discusses ...

J. B. Patton; P. Jayanetti

1996-08-01T23:59:59.000Z

109

Analysis on Control Method VSCF Wind Power System  

Science Conference Proceedings (OSTI)

By analyzing the operation behavior of an A.C. excited variable-speed constant-frequency (VSCF) wind-power generator, the field-oriented vector control technique and and the internal model controller (IMC) are transplanted into the voltage control of ... Keywords: Doubly-fed induction generator, pitch control, field oriented vector control, internal model controller, fuzzy-PD controller, Variable-speed constant frequency

Wang Yulong; Shao Guiping

2008-12-01T23:59:59.000Z

110

Interphase power controller adapted to the operating conditions of networks  

Science Conference Proceedings (OSTI)

This paper introduces a new family of Interphase Power Controller (ICP) for which the useful portion of the P{sub r}-{delta}{sub sr} characteristics is shifted as the power transfer level is increased. Thus, the power characteristics of a specific IPC application can be adapted to the operating conditions of the network. The response of the IPC is compared to those of the two conventional technologies used in building it: the phase-angle regulator and series compensation. It is shown how the natural response of the IPC regulates the active power passively, without need for control action. Also, the reactive power can be controlled independently of the active power allowing for better voltage control. The new IPC retains the inherent qualities of the previous IPCs.

Brochu, J.; Beauregard, F.; Morin, G.; Pelletier, P. [CITEQ, Varennes, Quebec (Canada)] [CITEQ, Varennes, Quebec (Canada)

1995-04-01T23:59:59.000Z

111

Centralized wind power plant voltage control with optimal power flow algorithm.  

E-Print Network (OSTI)

??This thesis presents a method of controlling the reactive power injected into a medium-voltage collection system by multiple wind turbine generators such that the voltage… (more)

Kline, Jared Andrew

2011-01-01T23:59:59.000Z

112

A learning control of unused energy power generation  

Science Conference Proceedings (OSTI)

In recent years, the development of new clean energy without dependence on fossil fuel has become urgent. This article proposes a learning control system for power generation using a low-temperature gap which has been designed to maintain the speed of ... Keywords: BP neural network, Evaporator, Learning control, Low thermal gap, Power generator, Turbine

Satomi Shikasho; Kun-Young Han; Ji-Sun Shin; Chui Chengyou; Hee-Hyol Lee

2010-12-01T23:59:59.000Z

113

Application of self-organizing systems in power systems control  

Science Conference Proceedings (OSTI)

The European electrical transmission network is operated increasingly close to its operational limits due to market integration and increased feed-in by renewable energies. For this reason, innovative solutions for a reliable, secure and efficient network ... Keywords: FACTS, multiagent systems, power flow control, power system control, self-organizing systems, smart grids

Sven C. Müller; Ulf Häger; Christian Rehtanz; Horst F. Wedde

2012-06-01T23:59:59.000Z

114

Hybrid Discrete and Continuous Control for Power Systems  

Science Conference Proceedings (OSTI)

The control of the electricity supply from generation to end-use has been an engineering and mathematical challenge for many decades. The continuous increase in power requirements, system interconnections and technological options prompted the search ... Keywords: electric systems, intelligent controls, power systems

W. H. Esselman; D. J. Sobajic; J. Maulbetsch

1999-11-01T23:59:59.000Z

115

ATPC: adaptive transmission power control for wireless sensor networks  

Science Conference Proceedings (OSTI)

Extensive empirical studies presented in this paper confirm that the quality of radio communication between low power sensor devices varies significantly with time and environment. This phenomenon indicates that the previous topology control solutions, ... Keywords: adaptive, feedback, link quality, transmission power control, wireless sensor network

Shan Lin; Jingbin Zhang; Gang Zhou; Lin Gu; John A. Stankovic; Tian He

2006-10-01T23:59:59.000Z

116

Nonlinear Control Techniques in Uninterruptible Power Supply Inverter: A Review  

Science Conference Proceedings (OSTI)

Summarizes the basic objectives of controllers for UPS system are tracking ability and robustness. To get this aims, many controllers have been proposed in the literature. In this paper a comprehensive review of the nonlinear control techniques of UPS ... Keywords: inverter, uninterruptible power supply, control techniques

Ghazanfar Shahgholian; Jawad Faiz; Pegah Shafaghi

2009-12-01T23:59:59.000Z

117

Bi-directional power control system for voltage converter  

DOE Patents (OSTI)

A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals.

Garrigan, Neil Richard (Niskayuna, NY); King, Robert Dean (Schenectady, NY); Schwartz, James Edward (Slingerlands, NY)

1999-01-01T23:59:59.000Z

118

Bi-directional power control system for voltage converter  

DOE Patents (OSTI)

A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals. 10 figs.

Garrigan, N.R.; King, R.D.; Schwartz, J.E.

1999-05-11T23:59:59.000Z

119

Dynamic control of grid power flow using controllable network transformers .  

E-Print Network (OSTI)

??The objective of the research is to develop a cost-effective, dynamic grid controller called the controllable network transformer (CNT) that can be implemented by augmenting… (more)

Das, Debrup

2011-01-01T23:59:59.000Z

120

Method for controlling power flow between an electrochemical cell and a power grid  

SciTech Connect

A method is disclosed for controlling a force-commutated inverter coupled between an electrochemical cell and a power grid for adjusting the magnitude and direction of the electrical energy flowing therebetween. Both the real power component and the reactive power component of ac electrical energy flow can be independently VARied through the switching waveform presented to the intermediately coupled inverter. A VAR error signal is derived from a comparison of a var command signal with a signal proportional to the actual reactive power circulating between the inverter and the power grid. This signal is presented to a voltage controller which essentially varies only the effective magnitude of the fundamental voltage waveform out of the inverter , thereby leaving the real power component substantially unaffected. In a similar manner, a power error signal is derived by a comparison of a power command signal with a signal proportional to the actual real power flowing between the electrochemical cell and the power grid. This signal is presented to a phase controller which varies only the phase of the fundamental component of the voltage waveform out of the inverter relative to that of the power grid and changes only the real power in proportion thereto, thus leaving the reactive power component substantially unaffected.

Coleman, A. K.

1981-02-17T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

An Approach to Autonomous Control for Space Nuclear Power Systems  

SciTech Connect

Under Project Prometheus, the National Aeronautics and Space Administration (NASA) investigated deep space missions that would utilize space nuclear power systems (SNPSs) to provide energy for propulsion and spacecraft power. The initial study involved the Jupiter Icy Moons Orbiter (JIMO), which was proposed to conduct in-depth studies of three Jovian moons. Current radioisotope thermoelectric generator (RTG) and solar power systems cannot meet expected mission power demands, which include propulsion, scientific instrument packages, and communications. Historically, RTGs have provided long-lived, highly reliable, low-power-level systems. Solar power systems can provide much greater levels of power, but power density levels decrease dramatically at {approx} 1.5 astronomical units (AU) and beyond. Alternatively, an SNPS can supply high-sustained power for space applications that is both reliable and mass efficient. Terrestrial nuclear reactors employ varying degrees of human control and decision-making for operations and benefit from periodic human interaction for maintenance. In contrast, the control system of an SNPS must be able to provide continuous operatio for the mission duration with limited immediate human interaction and no opportunity for hardware maintenance or sensor calibration. In effect, the SNPS control system must be able to independently operate the power plant while maintaining power production even when subject to off-normal events and component failure. This capability is critical because it will not be possible to rely upon continuous, immediate human interaction for control due to communications delays and periods of planetary occlusion. In addition, uncertainties, rare events, and component degradation combine with the aforementioned inaccessibility and unattended operation to pose unique challenges that an SNPS control system must accommodate. Autonomous control is needed to address these challenges and optimize the reactor control design.

Wood, Richard Thomas [ORNL; Upadhyaya, Belle R. [University of Tennessee, Knoxville (UTK)

2011-01-01T23:59:59.000Z

122

Study On The Self-Powered Active Vibration Control  

E-Print Network (OSTI)

A method of active vibration control using regenerated vibration energy, i.e., the self-powered active vibration control is proposed. In this system, vibration energy is regenerated with an electric generator ,which is called energy regenerative damper, and is stored in a condenser. An actuator attains active vibration control using the energy stored in the condenser. A variable resistance is used to control output force of the actuator. Since the damping coefficient of the energy regenerative damper is uncertain when it regenerates vibration energy, it is required for the controller to be robust to parameter uncertainty; H control method is applied to the system. Through experiments, the self-powered active control system is proved to have better isolation performance in comparison with that of a semi-active or a passive control system. INTRODUCTION Active vibration control has been applied to several systems. It has better isolation performance than a passive control system. Howe...

Yoshihiro Suda Institute; Yoshihiro Suda; Shigeyuki Nakadai; Kimihiko Nakano

1998-01-01T23:59:59.000Z

123

Interruptible load control for Taiwan Power Company  

SciTech Connect

Load management is the planning and implementation of those utility activities designed to influence customer use of electricity in ways that will produce desired changes in the utility's load shape. Interruptible load program is an option of load management which provides incentive rate to customers to interrupt or reduce the power demand during the system peak period or emergency condition. Therefore, how to design a proper incentive rate is the most important issue in implementing this program. This paper describes three alternatives designed for the interruptible load program, one of which was activated by Taiwan Power Company (Taipower) and some preliminary results were obtained. The effect of the interruptible load to the system peak demand reduction and the change of daily load curve for large industrial customers were analyzed. This paper estimates the avoided cost and design more appropriate incentive rate structure for interruptible load program.

Chen, C.S.; Leu, J.T. (Dept. of Electrical Engineering, National Sun Yat-Sen Univ., Kaohsiung (TW))

1990-05-01T23:59:59.000Z

124

Application of Newton's optimal power flow in voltage/reactive power control  

Science Conference Proceedings (OSTI)

This paper considers an application of Newton's optimal power flow to the solution of the secondary voltage/reactive power control in transmission networks. An efficient computer program based on the latest achievements in the sparse matrix/vector techniques has been developed for this purpose. It is characterized by good robustness, accuracy and speed. A combined objective function appropriate for various system load levels with suitable constraints, for treatment of the power system security and economy is also proposed. For the real-time voltage/reactive power control, a suboptimal power flow procedure has been derived by using the reduced set of control variables. This procedure is based on the sensitivity theory applied to the determination of zones for the secondary voltage/reactive power control and corresponding reduced set of regulating sources, whose reactive outputs represent control variables in the optimal power flow program. As a result, the optimal power flow program output becomes a schedule to be used by operators in the process of the real-time voltage/reactive power control in both normal and emergency operating states.

Bjelogrlic, M.; Babic, B.S. (Electric Power Board of Serbia, Belgrade (YU)); Calovic, M.S. (Dept. of Electrical Engineering, University of Belgrade, Belgrade (YU)); Ristanovic, P. (Institute Nikola Tesla, Belgrade (YU))

1990-11-01T23:59:59.000Z

125

Mercury Control Demonstration Projects Cover Photos: * Top: Limestone Power Plant  

NLE Websites -- All DOE Office Websites (Extended Search)

6 FEBRUARY 2008 6 FEBRUARY 2008 Mercury Control Demonstration Projects Cover Photos: * Top: Limestone Power Plant * Bottom left: AES Greenidge Power Plant * Bottom right: Presque Isle Power Plant A report on three projects conducted under separate cooperative agreements between the U.S. Department of Energy and: * Consol Energy * Pegasus Technologies * We Energies  Mercury Control Demonstration Projects Executive Summary ............................................................................ 4 Background ......................................................................................... 5 Mercury Removal Projects ................................................................ 7 TOXECON(tm) Retrofit For Mercury and Multi-Pollutant Control on Three 90-MW Coal-Fired Boilers ........................................7

126

The design of a smart controller for electric powered wheelchairs  

Science Conference Proceedings (OSTI)

Electric powered wheelchair (EPW) controllers have not seen substantial improvement since the introduction of the microprocessor. There are no features that warn the driver of danger or help keep the EPW under control in adverse conditions such as slipping ... Keywords: advanced wheelchair systems, controller, intelligent machines

Benjamin Salatin; Garrett Grindle; Hongwu Wang; Rory A. Cooper

2008-04-01T23:59:59.000Z

127

Optimal control of generator resynchronisation in electric power systems  

Science Conference Proceedings (OSTI)

Optimal control techniques are discussed for the resynchronisation of a steam turbine unit in an electric power system after it has lost synchronism. A time optimal control is derived and the resulting bang-bang control law is first simulated on an analogue ...

D. Rosenfeld; F. J. Evans

1972-11-01T23:59:59.000Z

128

Control and Power Management of Converter Fed Microgrids  

E-Print Network (OSTI)

1 Control and Power Management of Converter Fed Microgrids Charles K. Sao, Member, IEEE, and Peter in parallel in a VSC fed microgrid. Each current controlled VSC in such a microgrid has its own VPD/FQB controller that sets its current references to regulate the voltage and frequency of a common microgrid bus

Lehn, Peter W.

129

ELECTRIC POWER AND VENTILATION SYSTEM OF SILOE  

SciTech Connect

The 15-kv electric power of Siloe is supplied from a central substation, which serves all the laboratories in the Center. The substation transforms primary 3-phase power from 15 kv to 380 to 220 v. Control installations are supplied from sets of rectifiers and batteries with 127 and 48 v direct current. If the normal electric power supply fails, a 12000 kva diesel driven generator is automatically started and in a very short time supplies power. The ventilation system supplies the whole building with conditioned air, holds the shell in negative pressure, and exhausts radioactive effluents. (auth)

Mitault, G.; Faudou, J.-C.

1963-12-01T23:59:59.000Z

130

Interleaved power converter  

DOE Patents (OSTI)

A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

Zhu, Lizhi (Canton, MI)

2007-11-13T23:59:59.000Z

131

Digital control of power transients in a nuclear reactor  

Science Conference Proceedings (OSTI)

An integrated, closed-loop, control system for on-line operations in nuclear power plants has been developed and demonstrated with an LSI-11/23 micro-processor on the 5 MWt fission reactor (MITR-II) that is operated by the Massachusetts Institute of Technology. This control system has inherent capabilities to perform on-line fault diagnosis, information display, sensor calibration, and measurement estimation. Recently, its scope has been extended to include the direct digital control of power changes ranging from 20-80% of the reactor's licensed limit. This controller differs from most of those discussed in theoretical and simulation studies by recognizing the non-linearity of reactor dynamics, calculating reactivity on-line, and controlling the rate of change of power by restricting both period and reactivity. The controller functions accurately using rods of non-linear worth in the presence of nonlinear feedback effects.

Bernard, J.A.; Lanning, D.D.; Ray, A.

1984-02-01T23:59:59.000Z

132

Impact of inverter station on torsional dynamics of parallel HVdc-ac power system  

SciTech Connect

This paper investigates the impact of an inverter station on the torsional dynamics of a turbine-generator set which is located at the rectifier side of a parallel HVdc-ac power system. The studies show that depending on the stiffness of the inverter ac bus and electrical coupling between the inverter and rectifier ac buses, the inverter closed loop control can have noticeable contribution to the instability of torsional dynamics. This adverse torsional impact is observed in the study results even when the inverter ac bus is fairly strong (ESCR larger than 5.0).

Iravani, M.R.; Zhao, Z.; Hamouda, R.M. (Univ. of Toronto, Ontario (Canada). Dept. of Electrical Engineering)

1993-08-01T23:59:59.000Z

133

Precision envelope detector and linear rectifier circuitry  

DOE Patents (OSTI)

Disclosed is a method and apparatus for the precise linear rectification and envelope detection of oscillatory signals. The signal is applied to a voltage-to-current converter which supplies current to a constant current sink. The connection between the converter and the sink is also applied through a diode and an output load resistor to a ground connection. The connection is also connected to ground through a second diode of opposite polarity from the diode in series with the load resistor. Very small amplitude voltage signals applied to the converter will cause a small change in the output current of the converter, and the difference between the output current and the constant current sink will be applied either directly to ground through the single diode, or across the output load resistor, dependent upon the polarity. Disclosed also is a full-wave rectifier utilizing constant current sinks and voltage-to-current converters. Additionally, disclosed is a combination of the voltage-to-current converters with differential integrated circuit preamplifiers to boost the initial signal amplitude, and with low pass filtering applied so as to obtain a video or signal envelope output.

Davis, Thomas J. (Richland, WA)

1980-01-01T23:59:59.000Z

134

Cyber vulnerability in power systems operation and control  

Science Conference Proceedings (OSTI)

Modern power systems are composed of several interacting national systems synchronously or asynchronously interconnected over large geographic areas, and in the European case on a continental basis. In each country several areas are put under the control ...

Ettore Bompard; Paolo Cuccia; Marcelo Masera; Igor Nai Fovino

2012-01-01T23:59:59.000Z

135

Globally Optimal Distributed Power Control for Nonconcave Utility Maximization  

E-Print Network (OSTI)

Future wireless networks are expected to operate in dense environments where the system capacity is fundamentally limited by severe co-channel interference among neighboring links. Transmit-power control has been recently explored as an important interference-mitigation technique that aims to maximize a system efficiency metric, which is often measured by a system utility function. Optimal power control is known to be difficult to achieve, mainly because the optimization problem is in general highly non-convex. This problem had eluded researchers and remained open until our recent work [11], where a centralized optimal power control algorithm, referred to as MAPEL, is developed based on a monotonic optimization framework. However, there does not yet exist a distributed power control algorithm that achieves the global optimal solution for generic utility functions, although the distributed implementation is crucial for the wireless infrastructureless networks such as ad hoc and sensor networks. This paper fill...

Qian, Li Ping; Zhang,; Chiang, Mung

2011-01-01T23:59:59.000Z

136

Power quality control on the Romanian energy market  

Science Conference Proceedings (OSTI)

Power quality is one of the important objectives of the transmission and distribution network. The paper presents several aspects of the PQ monitoring interface between the transmission network and the distribution network. 110 kV voltage level, in view ... Keywords: control, energy market, power quality

A. S. Jude; P. Ehegardner; P. Andea; D. Vatau; F. M. Frigura-Iliasa

2009-05-01T23:59:59.000Z

137

Comparison of Prony and eigenanalysis for power system control design  

Science Conference Proceedings (OSTI)

This paper describes comparative results of direct (eigenanalysis) and indirect (Prony analysis) methods for generating frequency-domain data for power system control design. The methods are applied to the same model, a medium-scale model of the Midcontinent Area Power Pool (MAPP). Modal parameters (frequencies and damping) and transfer function poles and zeros are compared as calculated by the two methods.

Grund, C.E.; Paserba, J.J. (GE Industrial and Power Systems, Schenectady, NY (United States)); Hauer, J.F. (Bonneville Power Administration, Portland, OR (United States)); Nilsson, S. (Electric Power Research Inst., Palo Alto, CA (United States))

1993-08-01T23:59:59.000Z

138

Integrated Control of Active and Reactive Power Flow Controllers to Optimize Transmission System Utilization  

Science Conference Proceedings (OSTI)

Optimized power system control requires oversight of numerous control elements to efficiently and reliably transfer power across the system. The objective of this project was to minimize losses in the Consolidated Edison Electric power system via modification of control variables available to the system operator. These variables include generator voltages, transformer voltage/phase angle tap set points, and switched shunt status. System constraints include bus voltages, branch/interface flow limits, ...

2012-11-08T23:59:59.000Z

139

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices  

DOE Patents (OSTI)

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

Chassin, David P. (Pasco, WA); Donnelly, Matthew K. (Kennewick, WA); Dagle, Jeffery E. (Richland, WA)

2006-12-12T23:59:59.000Z

140

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices  

DOE Patents (OSTI)

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

Chassin, David P. (Pasco, WA); Donnelly, Matthew K. (Kennewick, WA); Dagle, Jeffery E. (Richland, WA)

2011-12-06T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Power Electronics-Based Transmission Controllers Reference Book  

Science Conference Proceedings (OSTI)

EPRI is sponsoring development of a first edition of the EPRI Power Electronics-Based Transmission Controllers Reference Book. The book will provide a broad overview on power electronics-based controllers—with information on historical perspectives, basic design considerations, factory testing, site installations, commissioning, operating performance, operation and maintenance, and future trends. The document will assist users in planning, developing, installing, and utilizing this technology.

2005-12-02T23:59:59.000Z

142

Simulator demonstration of the interphase power controller technology  

SciTech Connect

The paper reports on a simulator demonstration of the Interphase Power Controller (IPC) technology. The simulator models developed and the testing methodology are described. The main results confirm the basic attributes of the IPC (robust power flow control characteristic, fault current limitation and decoupling of the interconnected networks) and that the IPC can be built from conventional equipment. Random testing performed on the simulator proved to be useful in assessing the maximum stresses on the equipment.

Sybille, G.; Haj-Maharsi, Y. [Inst. de Recherche d`Hydro-Quebec, Varennes, Quebec (Canada)] [Inst. de Recherche d`Hydro-Quebec, Varennes, Quebec (Canada); Morin, G.; Beauregard, F.; Brochu, J.; Lemay, J.; Pelletier, P. [Centre d`Innovation sur le Transport d`Energie du Quebec, Varennes, Quebec (Canada)] [Centre d`Innovation sur le Transport d`Energie du Quebec, Varennes, Quebec (Canada)

1996-10-01T23:59:59.000Z

143

Model Predictive Control of Integrated Gasification Combined Cycle Power Plants  

SciTech Connect

The primary project objectives were to understand how the process design of an integrated gasification combined cycle (IGCC) power plant affects the dynamic operability and controllability of the process. Steady-state and dynamic simulation models were developed to predict the process behavior during typical transients that occur in plant operation. Advanced control strategies were developed to improve the ability of the process to follow changes in the power load demand, and to improve performance during transitions between power levels. Another objective of the proposed work was to educate graduate and undergraduate students in the application of process systems and control to coal technology. Educational materials were developed for use in engineering courses to further broaden this exposure to many students. ASPENTECH software was used to perform steady-state and dynamic simulations of an IGCC power plant. Linear systems analysis techniques were used to assess the steady-state and dynamic operability of the power plant under various plant operating conditions. Model predictive control (MPC) strategies were developed to improve the dynamic operation of the power plants. MATLAB and SIMULINK software were used for systems analysis and control system design, and the SIMULINK functionality in ASPEN DYNAMICS was used to test the control strategies on the simulated process. Project funds were used to support a Ph.D. student to receive education and training in coal technology and the application of modeling and simulation techniques.

B. Wayne Bequette; Priyadarshi Mahapatra

2010-08-31T23:59:59.000Z

144

Testing a new direct load control power line communication system  

SciTech Connect

South Carolina Electric and Gas is currently performing direct load control communications over power lines without using a power line carrier. This is the result of testing a load management system that combines the existing substation solid-state recording with voltage regulation capability. Using the solid-state recorder's extended control functions, the existing substation tap changer, a new patent-pending power line communications technique, and a patented voltage-step load control receiver, the system extends normal two-way communication between the utility operations and the substation with a one-way power line link to virtually any load. By varying the voltage level slightly, the system digitizes up to 32 different load control messages. The new voltage-step communication technique uses the substation's load tap changer to communicate one-way with the receivers over existing power lines. South Carolina Electric and Gas and the manufacturers have been performing a two-phase test of the load control system. Phase one testing showed that the percentage of successful load control message reception was 98%. Phase two testing is still in progress. Results to date show no deterioration of reception or equipment. Conclusions thus far are that the load management system is compatible with all installed utility equipment, and offers reliable direct load control.

Weers, D.D.; Shamsedin, M.A.

1987-07-01T23:59:59.000Z

145

Power system control centers: past, present, and future  

E-Print Network (OSTI)

In this paper, we review the functions and architectures of control centers: their past, present, and likely future. The evolving changes in power system operational needs require a distributed control center that is decentralized, integrated, flexible, and open. Present-day control centers are moving in that direction with varying degrees of success. The technologies employed in today’s control centers to enable them to be distributed are briefly reviewed. With the rise of the Internet age, the trend in information and communication technologies is moving toward Grid computing and Web services, or Grid services. A Grid service-based future control center is stipulated. Keywords—Computer control of power systems, control center, energy management system, SCADA. I.

Felix F. Wu; Khosrow Moslehi

2005-01-01T23:59:59.000Z

146

The interphase power controller: A new concept for managing power flow within AC networks  

SciTech Connect

The paper presents a new concept for controlling the flow of power within AC networks. The application is based on the series connection of impedances between different phases of the two (synchronous) subnetworks to be interconnected, hence its name: the Interphase Power Controller (IPC). The IPC acts as a current source with the following characteristics: the power flow is nearly constant (within 10%) for a wide range ([+-]25[degree]) of angle between the two subnetworks; there is no significant short-circuit contribution from one network to the other; severe contingencies on one side of the IPC have negligible impact on the voltage of the other side; no harmonics are generated (because there is no control action). Other operating conditions (reduced power, reactive power generation or absorption) are possible by switching impedance components. In all cases, the IPC comprises only conventional elements (transformer, capacitors, reactors, and circuit breakers).

Brochu, J.; Pelletier, P.; Beauregard, F.; Morin, G. (Citeq, Varennes, Quebec (Canada))

1994-04-01T23:59:59.000Z

147

Local control of reactive power by distributed photovoltaic generators  

SciTech Connect

High penetration levels of distributed photovoltaic (PV) generation on an electrical distribution circuit may severely degrade power quality due to voltage sags and swells caused by rapidly varying PV generation during cloud transients coupled with the slow response of existing utility compensation and regulation equipment. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We suggest a local control scheme that dispatches reactive power from each PV inverter based on local instantaneous measurements of the real and reactive components of the consumed power and the real power generated by the PVs. Using one adjustable parameter per circuit, we balance the requirements on power quality and desire to minimize thermal losses. Numerical analysis of two exemplary systems, with comparable total PV generation albeit a different spatial distribution, show how to adjust the optimization parameter depending on the goal. Overall, this local scheme shows excellent performance; it's capable of guaranteeing acceptable power quality and achieving significant saving in thermal losses in various situations even when the renewable generation in excess of the circuit own load, i.e. feeding power back to the higher-level system.

Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Sulc, Petr [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

148

Optimal Energy Storage Control Policies for the Smart Power Grid  

E-Print Network (OSTI)

Optimal Energy Storage Control Policies for the Smart Power Grid Iordanis Koutsopoulos Vassiliki is to devise an energy storage control policy that minimizes long-term average grid operational cost. The cost the stored energy. We prove that the policy is asymptotically optimal as the storage capacity becomes large

Koutsopoulos, Iordanis

149

Battery-State Dependent Power Control as a Dynamic Game  

E-Print Network (OSTI)

1 Battery-State Dependent Power Control as a Dynamic Game Ishai Menache and Eitan Altman Faculty number of mobile users with limited batteries. Whenever the battery drains out, the user pays a fixed price to recharge the battery. Users, assumed to have always traffic to send, control their transmission

150

Power flow management of microgrid networks using model predictive control  

Science Conference Proceedings (OSTI)

In this paper, we present a power flow management method for a network of cooperating microgrids within the context of a smart grid by formulating the problem in a model predictive control framework. In order to reliably and economically provide the ... Keywords: Microgrid, Model predictive control, Renewable energy sources, Smart grid, Storage devices

A. Hooshmand; H. A. Malki; J. Mohammadpour

2012-09-01T23:59:59.000Z

151

Hardwired Control Changes For NSTX DC Power Feeds  

SciTech Connect

The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. The original TFTR Hardwired Control System (HCS) with electromechanical relays was used for NSTX DC Power loop control and protection during NSTX operations. As part of the NSTX Upgrade, the HCS is being changed to a PLC-based system with the same control logic. This paper gives a description of the changeover to the new PLC-based system __________________________________________________

Ramakrishnan, S.

2013-06-28T23:59:59.000Z

152

Power and Frequency Control as it Relates to Wind-Powered Generation  

SciTech Connect

This report is a part of an investigation of the ability of the U.S. power system to accommodate large scale additions of wind generation. The objectives of this report are to describe principles by which large multi-area power systems are controlled and to anticipate how the introduction of large amounts of wind power production might require control protocols to be changed. The operation of a power system is described in terms of primary and secondary control actions. Primary control is fast, autonomous, and provides the first-line corrective action in disturbances; secondary control takes place on a follow-up time scale and manages the deployment of resources to ensure reliable and economic operation. This report anticipates that the present fundamental primary and secondary control protocols will be satisfactory as wind power provides an increasing fraction of the total production, provided that appropriate attention is paid to the timing of primary control response, to short term wind forecasting, and to management of reserves for control action.

Lacommare, Kristina S H

2010-12-20T23:59:59.000Z

153

Options for Control of Reactive Power by Distributed Photovoltaic Generators  

E-Print Network (OSTI)

High penetration levels of distributed photovoltaic(PV) generation on an electrical distribution circuit present several challenges and opportunities for distribution utilities. Rapidly varying irradiance conditions may cause voltage sags and swells that cannot be compensated by slowly responding utility equipment resulting in a degradation of power quality. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We discuss and compare via simulation various design options for control systems to manage the reactive power generated by these inverters. An important design decision that weighs on the speed and quality of communication required is whether the control should be centralized or distributed (i.e. local). In general, we find that local control schemes are capable for maintaining voltage within acceptable bounds. We consider the benefits of choosing different local variables on which to control and how the control system can be continuously tuned between robust voltage control, suitable for daytime operation when circuit conditions can change rapidly, and loss minimization better suited for nighttime operation.

Petr Sulc; Konstantin Turitsyn; Scott Backhaus; Michael Chertkov

2010-08-04T23:59:59.000Z

154

Active control of the resistive wall mode with power saturation  

SciTech Connect

An analytic model of non-linear feedback stabilization of the resistive wall mode is presented. The non-linearity comes from either the current or the voltage saturation of the control coil power supply. For the so-called flux-to-current control, the current saturation of active coils always results in the loss of control. On the contrary, the flux-to-voltage control scheme tolerates certain degree of the voltage saturation. The minimal voltage limit is calculated, below which the control will be lost.

Li Li; Liu Yue [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian, 116024 (China); Liu Yueqiang [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

2012-01-15T23:59:59.000Z

155

Photovoltaic Powering And Control System For Electrochromic Windows  

DOE Patents (OSTI)

A sealed insulated glass unit is provided with an electrochromic device for modulating light passing through the unit. The electrochromic device is controlled from outside the unit by a remote control electrically unconnected to the device. Circuitry within the unit may be magnetically controlled from outside. The electrochromic device is powered by a photovoltaic cells. The photovoltaic cells may be positioned so that at least a part of the light incident on the cell passes through the electrochromic device, providing a form of feedback control. A variable resistance placed in parallel with the electrochromic element is used to control the response of the electrochromic element to changes in output of the photovoltaic cell.

Schulz, Stephen C. (Tewksbury, MA); Michalski, Lech A. (Pennington, NJ); Volltrauer, Hermann N. (Englishtown, NJ); Van Dine, John E. (Faribault, MN)

2000-04-25T23:59:59.000Z

156

Options for Control of Reactive Power by Distributed Photovoltaic Generators  

E-Print Network (OSTI)

High penetration levels of distributed photovoltaic(PV) generation on an electrical distribution circuit present several challenges and opportunities for distribution utilities. Rapidly varying irradiance conditions may cause voltage sags and swells that cannot be compensated by slowly responding utility equipment resulting in a degradation of power quality. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We discuss and compare via simulation various design options for control systems to manage the reactive power generated by these inverters. An important design de...

Sulc, Petr; Backhaus, Scott; Chertkov, Michael

2010-01-01T23:59:59.000Z

157

Power-cable-carrier control (PC/sup 3/) system  

DOE Green Energy (OSTI)

A control system has been developed that uses a carrier signal imposed on an existing ac power circuit to transmit commands. This system was specifically developed to control an entire solar collector field by sending sun-tracking information to the trough collectors or by commanding them to assume safe positions (STOW) if out-of-limit conditions were encountered. Objectives were to develop a control system that operates reliably and has enough functions to control an entire collector field, yet do it at less cost than for conventional approaches. Development, design, operating characteristics, and field testing and results of the new system, the Power Cable Carrier Control (PC/sup 3/) System are described.

Alvis, R.L.; Wally, K.; Rosborough, J.R.

1981-04-01T23:59:59.000Z

158

Control and Optimization Meet the Smart Power Grid - Scheduling of Power Demands for Optimal Energy Management  

E-Print Network (OSTI)

The smart power grid aims at harnessing information and communication technologies to enhance reliability and enforce sensible use of energy. Its realization is geared by the fundamental goal of effective management of demand load. In this work, we envision a scenario with real-time communication between the operator and consumers. The grid operator controller receives requests for power demands from consumers, with different power requirement, duration, and a deadline by which it is to be completed. The objective is to devise a power demand task scheduling policy that minimizes the grid operational cost over a time horizon. The operational cost is a convex function of instantaneous power consumption and reflects the fact that each additional unit of power needed to serve demands is more expensive as demand load increases.First, we study the off-line demand scheduling problem, where parameters are fixed and known. Next, we devise a stochastic model for the case when demands are generated continually and sched...

Koutsopoulos, Iordanis

2010-01-01T23:59:59.000Z

159

The design of a 200 MW interphase power controller prototype  

SciTech Connect

The paper addresses the practical design aspects of a 200 MW prototype for the interconnection of two synchronous 120-kV networks that are close to their short-circuit limits. The Interphase Power Controller is a new concept for the control of active and reactive power; it uses only standard components connected in an original manner. The paper gives the results of EMTP simulations for the conditions governing the design of the components. The significant steady-state and transient capabilities of the components are given as well as insulation coordination and protection aspects. Finally, a preliminary layout is presented for the prototype.

Habashi, K.; Lombard, J.J.; Mourad, S. (ABB Canada, Inc., Montreal, Quebec (Canada)); Pelletier, P.; Morin, G.; Beauregard, F.; Brochu, J. (CITEQ, Varennes, Quebec (Canada))

1994-04-01T23:59:59.000Z

160

Reference Model for Control and Automation Systems in Electrical Power |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Model for Control and Automation Systems in Electrical Model for Control and Automation Systems in Electrical Power Reference Model for Control and Automation Systems in Electrical Power Modern infrastructure automation systems are threatened by cyber attack. Their higher visibility in recent years and the increasing use of modern information technology (IT) components contribute to increased security risk. A means of analyzing these infrastructure automation systems is needed to help understand and study the many system relationships that affect the overall security of the system. Modeling these systems is a very cost effective means of addressing the problem of security from an overall system view. The model presented in the document below provides a structured, cost effective approach to address technical security in process control systems

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

A control strategy for controllable series capacitor in electric power systems  

Science Conference Proceedings (OSTI)

It has been verified that a controllable series capacitor with a suitable control scheme can improve transient stability and help to damp electromechanical oscillations. A question of great importance is the selection of the input signals and a control ... Keywords: CLF and SIME method, CSC, Power oscillations

M. Ghandhari; G. Andersson; M. Pavella; D. Ernst

2001-10-01T23:59:59.000Z

162

Stability, Power Sharing, & Distributed Secondary Control in Droop-Controlled Microgrids  

E-Print Network (OSTI)

Stability, Power Sharing, & Distributed Secondary Control in Droop-Controlled Microgrids John W, Denmark Email: qsh@et.aau.dk Abstract--Motivated by the recent and growing interest in microgrids, we study the operation of droop-controlled DC/AC inverters in an islanded microgrid. We present a necessary

Bullo, Francesco

163

A holistic investigation of complexity sources in nuclear power plant control rooms  

E-Print Network (OSTI)

The nuclear power community in the United States is moving to modernize aging power plant control rooms as well as develop control rooms for new reactors. New generation control rooms, along with modernized control rooms, ...

Sasangohar, Farzan

2011-01-01T23:59:59.000Z

164

Communications and control for electric power systems: Final report  

Science Conference Proceedings (OSTI)

This report is a summary of some of the work done on the Communications and Control project, with particular emphasis on the achievements during the years 1986--1996. During those years, the project moved away from concern with dispersed storage and generation and its impact on power system operation (the team was responsible for studies in this area, and for making a power system simulator that included DSG), and became involved in more concrete work aimed at applying high-tech solutions to problems of power system communications and control. This report covers work done at JPL on the following topics: (1) the measurement of electric and magnetic fields, both ac and dc; (2) the use of optical power to supply low-power electronics; (3) the design of a fault-tolerant communication system designed for distribution automation; and (4) a digital phase locked loop that allows the use of low-power transmitting electronics to recreate a good-quality signal at the receiver. In a report of this kind, only the results and highlights of the work are described.

Kirkham, H.

1998-04-01T23:59:59.000Z

165

Computer controlled MHD power consolidation and pulse generation system  

DOE Green Energy (OSTI)

The major goal of this research project is to establish the feasibility of a power conversion technology which will permit the direct synthesis of computer programmable pulse power. Feasibility has been established in this project by demonstration of direct synthesis of commercial frequency power by means of computer control. The power input to the conversion system is assumed to be a Faraday connected MHD generator which may be viewed as a multi-terminal dc source and is simulated for the purpose of this demonstration by a set of dc power supplies. This consolidation/inversion (CI), process will be referred to subsequently as Pulse Amplitude Synthesis and Control (PASC). A secondary goal is to deliver a controller subsystem consisting of a computer, software, and computer interface board which can serve as one of the building blocks for a possible phase II prototype system. This report period work summarizes the accomplishments and covers the high points of the two year project. 6 refs., 41 figs.

Johnson, R.; Marcotte, K.; Donnelly, M.

1990-01-01T23:59:59.000Z

166

Electric Power Controller for Steering Wheel Management in Electric Cars  

E-Print Network (OSTI)

Electric Power Controller for Steering Wheel Management in Electric Cars Vicente Milanés, Joshué. An electric car has been equipped with the system designed and tests to prove the behavior of the system transportation systems. Among these topics, the automation of the actuators involved in the management of a car

Paris-Sud XI, Université de

167

PowerMatcher: multiagent control in the electricity infrastructure  

Science Conference Proceedings (OSTI)

Different driving forces push the electricity production towards decentralization. As a result, the current electricity infrastructure is expected to evolve into a network of networks, in which all system parts communicate with each other and influence ... Keywords: electrical power systems automation, electricity infrastructure, electronic markets, multi-agent control, multi-agent systems

J. K. Kok; C. J. Warmer; I. G. Kamphuis

2005-07-01T23:59:59.000Z

168

Enhanced IGCC regulatory control and coordinated plant-wide control strategies for improving power ramp rates  

SciTech Connect

As part of ongoing R&D activities at the National Energy Technology Laboratory’s (NETL) Advanced Virtual Energy Simulation Training & Research (AVESTAR™) Center, this paper highlights strategies for enhancing low-level regulatory control and system-wide coordinated control strategies implemented in a high-fidelity dynamic simulator for an Integrated Gasification Combined Cycle (IGCC) power plant with carbon capture. The underlying IGCC plant dynamic model contains 20 major process areas, each of which is tightly integrated with the rest of the power plant, making individual functionally-independent processes prone to routine disturbances. Single-loop feedback control although adequate to meet the primary control objective for most processes, does not take into account in advance the effect of these disturbances, making the entire power plant undergo large offshoots and/or oscillations before the feedback action has an opportunity to impact control performance. In this paper, controller enhancements ranging from retuning feedback control loops, multiplicative feed-forward control and other control techniques such as split-range control, feedback trim and dynamic compensation, applicable on various subsections of the integrated IGCC plant, have been highlighted and improvements in control responses have been given. Compared to using classical feedback-based control structure, the enhanced IGCC regulatory control architecture reduces plant settling time and peak offshoots, achieves faster disturbance rejection, and promotes higher power ramp-rates. In addition, improvements in IGCC coordinated plant-wide control strategies for “Gasifier-Lead”, “GT-Lead” and “Plantwide” operation modes have been proposed and their responses compared. The paper is concluded with a brief discussion on the potential IGCC controller improvements resulting from using advanced process control, including model predictive control (MPC), as a supervisory control layer.

Mahapatra, P.; Zitney, S.

2012-01-01T23:59:59.000Z

169

Adaptive stabilizing control of a power system through UPFC shunt and series converters  

Science Conference Proceedings (OSTI)

The dynamic performance of a power system can be improved by using additional controls in a unified power flow controller (UPFC). Self-tuning adaptive control of the voltage magnitude of the series converter and phase angle of shunt converter for stabilization ... Keywords: UPFC, adaptive control, on-line identification, pole - shifting control, power system stabilizing control

A. H. M. A. Rahim; E. P. Nowicki

2007-07-01T23:59:59.000Z

170

The Guy at the Controls: Labor Quality and Power Plant Efficiency  

E-Print Network (OSTI)

Controls: Labor Quality and Power Plant Efficiency July 2007Controls: Labor Quality and Power Plant E ciency James B.on the fuel e ciency of power plants. Although electricity

Bushnell, Jim B; Wolfram, Catherine D

2007-01-01T23:59:59.000Z

171

Soft-stall control versus furling control for small wind turbine power regulation  

DOE Green Energy (OSTI)

Many small wind turbines are designed to furl (turn) in high winds to regulate power and provide overspeed protection. Furling control results in poor energy capture at high wind speeds. This paper proposes an alternative control strategy for small wind turbines -- the soft-stall control method. The furling and soft-stall control strategies are compared using steady state analysis and dynamic simulation analysis. The soft-stall method is found to offer several advantages: increased energy production at high wind speeds, energy production which tracks the maximum power coefficient at low to medium wind speeds, reducing furling noise, and reduced thrust.

Muljadi, E.; Forsyth, T.; Butterfield, C.P.

1998-07-01T23:59:59.000Z

172

COMMERCIAL UTILITY PERSPECTIVES ON NUCLEAR POWER PLANT CONTROL ROOM MODERNIZATION  

SciTech Connect

Commercial nuclear power plants (NPPs) in the United States need to modernize their main control rooms (MCR). Many NPPs have done partial upgrades with some success and with some challenges. The Department of Energy’s (DOE) Light Water Reactor Sustainability (LWRS) Program, and in particular the Advanced Instrumentation and Controls (I&C) and Information Systems Technologies Research and Development (R&D) Pathway within LWRS, is designed to assist commercial nuclear power industry with their MCR modernization efforts. As part of this framework, a survey was issued to utility representatives of the LWRS Program Advanced Instrumentation, Information, and Control Systems/Technologies (II&C) Utility Working Group to obtain their views on a range of issues related to MCR modernization, including: drivers, barriers, and technology options, and the effects these aspects will have on concepts of operations, modernization strategies, and staffing. This paper summarizes the key survey results and discusses their implications.

Jeffrey C. Joe; Ronald L. Boring; Julius J. Persensky

2012-07-01T23:59:59.000Z

173

Energy efficient control for power management circuits operating from nano-watts to watts  

E-Print Network (OSTI)

Energy efficiency and form factor are the key driving forces in today's power electronics. All power delivery circuits, irrespective of the magnitude of power, basically consists of power trains, gate drivers and control ...

Bandyopadhyay, Saurav

2013-01-01T23:59:59.000Z

174

Advanced underground Vehicle Power and Control: The locomotive Research Platform  

DOE Green Energy (OSTI)

Develop a fuelcell mine locomotive with metal-hydride hydrogen storage. Test the locomotive for fundamental limitations preventing successful commercialization of hydride fuelcells in underground mining. During Phase 1 of the DOE-EERE sponsored project, FPI and its partner SNL, completed work on the development of a 14.4 kW fuelcell power plant and metal-hydride energy storage. An existing battery-electric locomotive with similar power requirements, minus the battery module, was used as the base vehicle. In March 2001, Atlas Copco Wagner of Portland, OR, installed the fuelcell power plant into the base vehicle and initiated integration of the system into the vehicle. The entire vehicle returned to Sandia in May 2001 for further development and integration. Initial system power-up took place in December 2001. A revision to the original contract, Phase 2, at the request of DOE Golden Field Office, established Vehicle Projects LLC as the new prime contractor,. Phase 2 allowed industry partners to conduct surface tests, incorporate enhancements to the original design by SNL, perform an extensive risk and safety analysis, and test the fuelcell locomotive underground under representative production mine conditions. During the surface tests one of the fuelcell stacks exhibited reduced power output resulting in having to replace both fuelcell stacks. The new stacks were manufactured with new and improved technology resulting in an increase of the gross power output from 14.4 kW to 17 kW. Further work by CANMET and Hatch Associates, an engineering consulting firm specializing in safety analysis for the mining industry, both under subcontract to Vehicle Projects LLC, established minimum requirements for underground testing. CANMET upgraded the Programmable Logic Control (PLC) software used to monitor and control the fuelcell power plant, taking into account locomotive operator's needs. Battery Electric, a South Africa manufacturer, designed and manufactured (at no cost to the project) a new motor controller capable of operating the higher rpm motor and different power characteristics of the fuelcells. In early August 2002, CANMET, with the technical assistance of Nuvera Fuel Cells and Battery Electric, installed the new PLC software, installed the new motor controller, and installed the new fuelcell stacks. After minor adjustments, the fuelcell locomotive pulled its first fully loaded ore cars on a surface track. The fuelcell-powered locomotive easily matched the battery powered equivalent in its ability to pull tonnage and equaled the battery-powered locomotive in acceleration. The final task of Phase 2, testing the locomotive underground in a production environment, occurred in early October 2002 in a gold mine. All regulatory requirements to allow the locomotive underground were completed and signed off by Hatch Associates prior to going underground. During the production tests, the locomotive performed flawlessly with no failures or downtime. The actual tests occurred during a 2-week period and involved moving both gold ore and waste rock over a 1,000 meter track. Refueling, or recharging, of the metal-hydride storage took place on the surface. After each shift, the metal-hydride storage module was removed from the locomotive, transported to surface, and filled with hydrogen from high-pressure tanks. The beginning of each shift started with taking the fully recharged metal-hydride storage module down into the mine and re-installing it onto the locomotive. Each 8 hour shift consumed approximately one half to two thirds of the onboard hydrogen. This indicates that the fuelcell-powered locomotive can work longer than a similar battery-powered locomotive, which operates about 6 hours, before needing a recharge.

Vehicle Projects LLC

2003-01-28T23:59:59.000Z

175

HTGR power plant turbine-generator load control system  

SciTech Connect

A control system is disclosed for a high temperature gas cooled reactor power plant, wherein a steam source derives heat from the reactor coolant gas to generate superheated and reheated steam in respective superheater and reheater sections that are included in the steam source. Each of dual turbine-generators includes a high pressure turbine to pass superheated steam and an associated intermediate low pressure turbine to pass reheated steam. A first admission valve means is connected to govern a flow of superheated steam through a high pressure turbine, and a second admission valve means is connected to govern a flow of reheated steam through an intermediate-low pressure turbine. A bypass line and bypass valve means connected therein are connected across a second admission valve means and its intermediate-low pressure turbine. The second admission valve means is positioned to govern the steam flow through the intermediate-low pressure turbine in accordance with the desired power output of the turbine-generator. In response to the steam flow through the intermediate-low pressure turbine, the bypass valve means is positioned to govern the steam flow through the bypass line to maintain a desired minimum flow through the reheater section at times when the steam flow through the intermediate-low pressure turbine is less than such minimum. The power output of the high pressure turbine is controlled by positioning the first admission valve means in predetermined proportionality with the desired power output of the turbine-generator, thereby improving the accuracy of control of the power output of the high pressure turbine at low load levels.

Braytenbah, A.S.; Jaegtnes, K.O.

1976-12-28T23:59:59.000Z

176

Measurement and control techniques in geothermal power plants  

DOE Green Energy (OSTI)

This information provided the background and source material used in preparing the chapter of the Geothermal Source Book on instrumentation, measurement, and control techniques. Here more complete and detailed information is presented than could be included in the source book chapter and is being published for reference. Included are detailed examples of instrumentation and control techniques currently being used in geothermal power plants. In addition, the basic guidelines and unique characteristics of instrumentation and control in geothermal systems, are presented. The instrumentation and control philosophy and the hardware involved in geothermal electric plants and their supply and injection systems are addressed. The intent is to address the unique characteristics of geothermal electric instrumentation and control (I and C) systems. Standard I and C practice is available in the general literature. Sources of information for standard I and C practice are listed in the Appendix. The information presents the philosophy of I and C system design; the development of the system, from power grid considerations through subsystem operation to specific system details; and component selection and operating considerations.

Whitbeck, J.F.; Dart, R.H.; Miller, J.D.; Brewer, D.R.

1979-01-01T23:59:59.000Z

177

A Control Strategy for Off-Grid Solar Photovoltaic Power System Based on MPPT Algorithm  

Science Conference Proceedings (OSTI)

Off-grid solar photovoltaic (PV) power system characteristics are used widely in many far-away areas during theses years. The new control strategy employs Maximum Power Point Tracking (MPPT) algorithm. The maximum power point tracker is a high efficiency ... Keywords: off-grid solar photovoltaic power system, maximum power point tracking algorithm, perturbation and observation control method

Tianjian Wang; Xia Dang; Dong Liu

2012-10-01T23:59:59.000Z

178

NREL: Wind Research - NREL and EPRI Actively Embrace Active Power Control  

NLE Websites -- All DOE Office Websites (Extended Search)

and EPRI Actively Embrace Active Power Control Systems for Wind Power and EPRI Actively Embrace Active Power Control Systems for Wind Power December 2, 2013 The Second Workshop on Active Power Control (APC) cohosted by the National Renewable Energy Laboratory (NREL) and the Electric Power Research Institute (EPRI) in Broomfield, Colorado, last May drew more than 60 industry experts from around the world to participate in a comprehensive discussion about the need for and impacts of active power controls from wind plants. Various forms of active power control can help stabilize the grid by enabling generating sources to increase or decrease power output to meet the constantly fluctuating needs of meeting the load demand and avoid events that can cause brownouts and power failures. The three forms of active power control discussed during the workshop were inertial control,

179

Neural network predictive control of UPFC for improving transient stability performance of power system  

Science Conference Proceedings (OSTI)

This paper presents a neural network predictive controller for the UPFC to improve the transient stability performance of the power system. A neural network model for the power system is trained using the backpropagation learning method employing the ... Keywords: Identification, Neural networks, Power system transient stability, Predictive control, Unified power flow controller (UPFC)

Sheela Tiwari; Ram Naresh; R. Jha

2011-12-01T23:59:59.000Z

180

A power adjusting algorithm on mobility control in mobile ad hoc networks  

Science Conference Proceedings (OSTI)

Power saving is one of the key issues in mobile ad-hoc networks (MANET), while previous researches in MAC layer are mostly focused on improving the channel utilization by adopting variable-range transmission power control. In this paper we focus on the ... Keywords: dynamic source routing (DSR), mobile ad-hoc networks (MANETs), mobility control, power control, power efficiency

Jianrui Yuan; Jintao Meng

2011-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Fuzzy Modeling of Uplink Transmit Power Control in a CDMA Network.  

E-Print Network (OSTI)

??From its beginning, transmit power has always placed a significant constraint on the performance of wireless radio systems. The transmit power control problem can be… (more)

Uzoechi, Victor

2008-01-01T23:59:59.000Z

182

THE SYSTEM OF POWER SUPPLIES, CONTROL AND MODULATION OF ELECTRON GUN FOR FREE ELECTRON LASER  

E-Print Network (OSTI)

. The output of power inverter is connected to input coil of isolated power transformer (300kV). Timer Electric power for part 2 goes from power inverter through isolated power transformer (isolation voltageTHE SYSTEM OF POWER SUPPLIES, CONTROL AND MODULATION OF ELECTRON GUN FOR FREE ELECTRON LASER E

Kozak, Victor R.

183

The effect of high penetration of wind power on primary frequency control of power systems.  

E-Print Network (OSTI)

??In this work, a power system with wind power units and hydro power units are considered. The hydro power unit and variable speed wind turbine… (more)

Motamed, Bardia

2013-01-01T23:59:59.000Z

184

Combining Droop Curve Concepts with Control Systems for Wind Turbine Active Power Control: Preprint  

DOE Green Energy (OSTI)

Wind energy is becoming a larger portion of the global energy portfolio and wind penetration has increased dramatically in certain regions of the world. This increasing wind penetration has driven the need for wind turbines to provide active power control (APC) services to the local utility grid, as wind turbines do not intrinsically provide frequency regulation services that are common with traditional generators. It is common for large scale wind turbines to be decoupled from the utility grid via power electronics, which allows the turbine to synthesize APC commands via control of the generator torque and blade pitch commands. Consequently, the APC services provided by a wind turbine can be more flexible than those provided by conventional generators. This paper focuses on the development and implementation of both static and dynamic droop curves to measure grid frequency and output delta power reference signals to a novel power set point tracking control system. The combined droop curve and power tracking controller is simulated and comparisons are made between simulations using various droop curve parameters and stochastic wind conditions. The tradeoffs involved with aggressive response to frequency events are analyzed. At the turbine level, simulations are performed to analyze induced structural loads. At the grid level, simulations test a wind plant's response to a dip in grid frequency.

Buckspan, A.; Aho, J.; Pao, L.; Fleming, P.; Jeong, Y.

2012-06-01T23:59:59.000Z

185

Combining Droop Curve Concepts with Control Systems for Wind Turbine Active Power Control: Preprint  

SciTech Connect

Wind energy is becoming a larger portion of the global energy portfolio and wind penetration has increased dramatically in certain regions of the world. This increasing wind penetration has driven the need for wind turbines to provide active power control (APC) services to the local utility grid, as wind turbines do not intrinsically provide frequency regulation services that are common with traditional generators. It is common for large scale wind turbines to be decoupled from the utility grid via power electronics, which allows the turbine to synthesize APC commands via control of the generator torque and blade pitch commands. Consequently, the APC services provided by a wind turbine can be more flexible than those provided by conventional generators. This paper focuses on the development and implementation of both static and dynamic droop curves to measure grid frequency and output delta power reference signals to a novel power set point tracking control system. The combined droop curve and power tracking controller is simulated and comparisons are made between simulations using various droop curve parameters and stochastic wind conditions. The tradeoffs involved with aggressive response to frequency events are analyzed. At the turbine level, simulations are performed to analyze induced structural loads. At the grid level, simulations test a wind plant's response to a dip in grid frequency.

Buckspan, A.; Aho, J.; Pao, L.; Fleming, P.; Jeong, Y.

2012-06-01T23:59:59.000Z

186

Study of operation of a current-controlled power inverter with hysteretic current controllers under various control options  

SciTech Connect

Inverters with hysteretic current controllers have constituted one of the most common types of CD/AC power converters. They are used in high-performance AC drive systems and as a source of reactive power of power-conditioning systems. Their main feature consists in the presence of a current feedback which allows the avoidance sophisticated open-loop control strategies. Existing current-controlled inverters with hysteretic current controllers (CCI-HCC) result in the dependence of the inverter on its load characteristics, poor inverter utilization due to too much or too little supply voltage, and the current error in the tolerance band which causes deterioration of operation of the supplied motor. In this work, techniques and results of modeling the operation of a current-controlled three-phase power inverter with hysteretic current controllers are presented. Four symmetrical control options are considered: the so called independent type, semi-dependent type (a), semi-dependent type (b), and dependent type, each using three current controllers. Performance indices of an exemplary inverter-induction motor set and a RL-loaded inverter with two different mechanical loads and time constants, otherwise difficult to compute, were determined.

Rashidi, N.H.

1988-01-01T23:59:59.000Z

187

Alternative Fuels Data Center: Students Power Remote-Controlled Cars With  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Students Power Students Power Remote-Controlled Cars With Biodiesel to someone by E-mail Share Alternative Fuels Data Center: Students Power Remote-Controlled Cars With Biodiesel on Facebook Tweet about Alternative Fuels Data Center: Students Power Remote-Controlled Cars With Biodiesel on Twitter Bookmark Alternative Fuels Data Center: Students Power Remote-Controlled Cars With Biodiesel on Google Bookmark Alternative Fuels Data Center: Students Power Remote-Controlled Cars With Biodiesel on Delicious Rank Alternative Fuels Data Center: Students Power Remote-Controlled Cars With Biodiesel on Digg Find More places to share Alternative Fuels Data Center: Students Power Remote-Controlled Cars With Biodiesel on AddThis.com... April 14, 2012 Students Power Remote-Controlled Cars With Biodiesel

188

Title: “ENERGY MANAGEMENT OF MARINE ELECTRICAL POWER SYSTEMS – CONTROL OF INTEGRATED, AUTONOMOUS POWER SYSTEMS”  

E-Print Network (OSTI)

Norpropeller. Electric propulsion will provide better vessel manouverability, system redundancy and higher flexibility with engine room arrangement, Ĺdnanes (2003). On vessels where there is a large variation in load demand reduced fuel consumption and optimal power/energy management may be regarded as advantages that are still not fully utilized. In that respect, the new equipment and modern control systems can provide new possibilities for improving present control strategies, performance, and utilization of the installation. It is also expected that an improved control system should provide overall higher level of safety and reliability. The present state of the art type of tools and methods for analyzing combined power systems does only to a limited extent utilize the possibilities for increased knowledge available in the more advanced models and methods developed and used within each of the machinery and electrical engineering disciplines. To be able to analyze increasingly more complex systems of interest, the ability to easily combine models and methods to develop more fundamental insight into the total systems behavior, its characteristics and limitations will be an advantage in design of new systems. According to that it is first necessary to design the power system simulation model which should include mathematical models of electrical and mechanical machinery components to the required level

unknown authors

2004-01-01T23:59:59.000Z

189

Air Cooling Technology for Power Electronics Thermal Control (Presentation)  

DOE Green Energy (OSTI)

Assessing potential for air cooling in power electronics is a critical factor in power electronics equipment. NREL aims to assess effective air cooling techniques for power electronics technologies.

Bharathan, D.

2007-11-14T23:59:59.000Z

190

Controller Design of Power Quality-Improving Appliances  

SciTech Connect

This paper presents an innovative solution to power quality problems -- using power quality improving (PQI) appliances to reduce harmonic currents and improve the power factor in buildings.

Hammerstrom, Donald J.; Zhou, Ning; Lu, Ning

2007-01-01T23:59:59.000Z

191

Reference Model for Control and Automation Systems in Electrical Power  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reference Model Reference Model for Control and Automation Systems in Electrical Power Version 1.2 October 12, 2005 Prepared by: Sandia National Laboratories' Center for SCADA Security Jason Stamp, Technical Lead Michael Berg, Co-Technical Lead Michael Baca, Project Lead This work was conducted for the DOE Office of Electricity Delivery and Energy Reliability under Contract M64SCADSNL Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. 2 Contents 1 Executive Summary.................................................................................................3 2 Introduction..............................................................................................................4

192

Nuclear Power Advisory Meeting: Instrumentation and Control Briefing Book  

Science Conference Proceedings (OSTI)

This document combines the material previously included in the Instrumentation and Control (I&C) Briefing Book for the Nuclear Power Advisory Meeting with the annual I&C research plan, replacing the latter document. It contains key information on the program and its projects including: 1. Program executive summary a high level document on the key activities of the I&C base program as well as its three supplemental groups 2. A consolidated list of EPRI I&C program deliverables for the next three years 3. ...

2011-08-18T23:59:59.000Z

193

Superior Valley photovoltaic power processing and system controller evaluation  

DOE Green Energy (OSTI)

Sandia National Laboratories, sponsored by the US Department of Energy`s Office of Energy Management, conducts the photovoltaic balance-of-system program. Under this program, Sandia supports the Department of Defense Strategic Environmental Research Development Plan, SERDP, which is advancing the use of photovoltaics in operational DoD facilities. This report details the acceptance testing of the first of these photovoltaic hybrid systems: the Superior Valley photovoltaic-diesel hybrid system. This is the first of several photovoltaic installations for the Department of Defense. The system hardware tested at Sandia included an inverter, maximum power trackers, and a system controller.

Bonn, R.; Ginn, J.; Zirzow, J.; Sittler, G.

1995-11-01T23:59:59.000Z

194

Power System Control Practices and Outlook for New or Revised Control Concepts  

Science Conference Proceedings (OSTI)

This research reviews the capability of current power system control practices in North America to address open access to the transmission system. In a deregulated, competitive environment, with non-traditional suppliers entering energy markets, redefined rules are needed to ensure continued reliable and stable operation of the interconnected grids and to reasonably allocate the control burden among both regulated and non-regulated suppliers.

1994-09-02T23:59:59.000Z

195

Point Defect Control in Power III-Nitride Semiconductors  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and ... Characterization of Degradation for MLCC under Thermal and Electrical ...

196

Switching power supply  

DOE Patents (OSTI)

The invention is a repratable capacitor charging, switching power supply. A ferrite transformer steps up a dc input. The transformer primary is in a full bridge configuration utilizing power MOSFETs as the bridge switches. The transformer secondary is fed into a high voltage, full wave rectifier whose output is connected directly to the energy storage capacitor. The transformer is designed to provide adequate leakage inductance to limit capacitor current. The MOSFETs are switched to the variable frequency from 20 to 50 kHz to charge a capacitor from 0.6 kV. The peak current in a transformer primary and secondary is controlled by increasing the pulse width as the capacitor charges. A digital ripple counter counts pulses and after a preselected desired number is reached an up-counter is clocked.

Mihalka, A.M.

1984-06-05T23:59:59.000Z

197

Control of hydrogen sulfide emission from geothermal power plants  

DOE Green Energy (OSTI)

A process for controlling H/sub 2/S emissions at geothermal power plants was evaluated in laboratory scale equipment and by process engineering analysis. The process is based on scrubbing geothermal steam with a metal salt solution to selectively remove and precipitate the contained H/sub 2/S. The metal sulfide is roasted or oxygen/acid leached to regenerate the metal salt, and sulfur is rejected from the system as elemental sulfur or as sulfate. Up to 95 percent removal of H/sub 2/S from simulated geothermal steams was obtained in a 2'' diameter scrubbing column packed with 3 feet of 5/8'' Flexirings by use of a recirculating slurry of copper sulfate/copper sulfide. Information is included on the chemistry, thermodynamics, kinetics and process control aspects of the process, scrubber system design, operation, and corrosion, and design proposals and cost estimates for a H/sub 2/S removal system. (LCL)

Harvey, W.W.; Brown, F.C.; Turchan, M.J.

1976-07-01T23:59:59.000Z

198

Microprocessor systems and architectures for applications to the control and protection of electric power systems  

Science Conference Proceedings (OSTI)

Some design concepts for microprocessor applications to the control and protection of electric power systems are presented. A formal design methodology is outlined. Present microprocessor applications to the control and protection of the electric power ...

Dale I. Rummer; Mladen Kezunovic

1979-04-01T23:59:59.000Z

199

IEC 61400-25 protocol based monitoring and control protocol for tidal current power plant  

Science Conference Proceedings (OSTI)

Wind energy and tidal current power have a common operation principle. Tidal current power converts kinetic energy of fluid to electric power. The communication infrastructure is very important to control the system and to monitor the working conditions ... Keywords: IEC 61400-25, monitoring, remote control, tidal current power

Jung Woo Kim; Hong Hee Lee

2010-09-01T23:59:59.000Z

200

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high-power power supply produces a controllable, constant high voltage put under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules. 5 figs.

Shimer, D.W.; Lange, A.C.

1996-10-15T23:59:59.000Z

202

The AGS main magnet power supply upgrade  

SciTech Connect

The AGS Main Magnet Power Supply consists of a group of thyristor controlled power converters that operate from full rectify to full invert. In order to minimize ripple during the critical periods of injection and extraction 24 pulse converters are used for these portions of the cycle. The maximum voltage available in this mode is nominally 2,000 volts. The converters that are functional during this portion of the cycle are called the flat-top bank or ``F`` bank modules. During acceleration and invert where voltages of up to 12,000 volts are needed and where the ripple requirements are less stringent, groups of twelve pulse converters are operational. These converters are called the Pulsed bank or ``P`` bank modules. The original controlled rectifier system consisted of 96 large mercury filled excitron tubes divided equally between the P bank and F bank converters. These devices were extremely durable and ran successfully for over twenty years. It was, decided to replace the excitron farm with multiple arrangements of three-phase, full-wave, bridge modules that utilize silicon controlled rectifiers (SCR`s or thyristors) as the switching element. In order to match the existing transformer connections and buswork, eight identical modules were required; four for the P bank system and four for the F bank system. In order to reduce noise pickup and provide electrical isolation the high level SCR gate triggers are provided via fiberoptic cable. The status of various parameters such as water flow, auxiliary power supply performance, trigger circuitry failure, over voltage, overcurrent, and loss of phase reference are monitored via a programmable logic controller (PLCs). The PLCs use isolated input and output modules for various voltage levels from TTL to 150 Vdc to 125 Vac. These devices are extremely flexible and have allowed modifications and improvements that have enhanced the performance over any equivalent hard wired system.

Sandberg, J.N.; Casella, R.; Geller, J.; Marneris, I.; Soukas, A.; Schumburg, N.

1995-05-01T23:59:59.000Z

203

PAPER ACCEPTED TO IEEE TRANSACTIONS ON POWER SYSTEMS, Nov. 2008 1 Reactive Power and Voltage Control in Distribution  

E-Print Network (OSTI)

PAPER ACCEPTED TO IEEE TRANSACTIONS ON POWER SYSTEMS, Nov. 2008 1 Reactive Power and Voltage) problem associated with reactive power and voltage control in distribution systems to minimize daily on the number of switching operations of transformer load tap changers (LTCs) and capacitors, which are modeled

Cañizares, Claudio A.

204

INFORMATION INTEGRATION IN CONTROL ROOMS AND TECHNICAL OFFICES IN NUCLEAR POWER PLANTS  

E-Print Network (OSTI)

Information integration in control rooms and technical offices in nuclear power plants Report prepared within the framework of the

unknown authors

2001-01-01T23:59:59.000Z

205

Brief Fuzzy wide-range control of fossil power plants for life extension and robust performance  

Science Conference Proceedings (OSTI)

This paper presents a fuzzy-logic-based methodology of life extending control (LEC) for robust wide-range operation of fossil power plants including load-following, scheduled shutdown, and hot startup. The objectives of the LEC are performance enhancement ... Keywords: Fuzzy control, Gain scheduling, Life extending control, Power plant control, Robust control

P. Kallappa; Asok Ray

2000-01-01T23:59:59.000Z

206

A theory for comparing the expressive power of access control models  

Science Conference Proceedings (OSTI)

We present a theory for comparing the expressive power of access control models. The theory is based on simulations that preserve security properties. We perceive access control systems as state-transition systems and present two kinds of simulations, ... Keywords: Access control, access matrix, discretionary access control, expressive power, reduction, role-based access control, state-matching reduction, trust management

Mahesh V. Tripunitara; Ninghui Li

2007-04-01T23:59:59.000Z

207

Precision control of high temperature furnaces using an auxiliary power supply and charged particle current flow  

DOE Patents (OSTI)

Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved. 5 figs.

Pollock, G.G.

1997-01-28T23:59:59.000Z

208

Precision control of high temperature furnaces using an auxiliary power supply and charged practice current flow  

DOE Patents (OSTI)

Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved.

Pollock, George G. (San Ramon, CA)

1997-01-01T23:59:59.000Z

209

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

to manipulate the electrical power delivered to the grid 2 .turbine pitch and of electrical power output can be used torelationship between electrical power and frequency, or to

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

210

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

of large amounts of wind power production might requirewill be satisfactory as wind power provides an increasing64   7.2   Wind Power in Relation to System

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

211

Tutorial of Wind Turbine Control for Supporting Grid Frequency through Active Power Control: Preprint  

DOE Green Energy (OSTI)

As wind energy becomes a larger portion of the world's energy portfolio and wind turbines become larger and more expensive, wind turbine control systems play an ever more prominent role in the design and deployment of wind turbines. The goals of traditional wind turbine control systems are maximizing energy production while protecting the wind turbine components. As more wind generation is installed there is an increasing interest in wind turbines actively controlling their power output in order to meet power setpoints and to participate in frequency regulation for the utility grid. This capability will be beneficial for grid operators, as it seems possible that wind turbines can be more effective at providing some of these services than traditional power plants. Furthermore, establishing an ancillary market for such regulation can be beneficial for wind plant owner/operators and manufacturers that provide such services. In this tutorial paper we provide an overview of basic wind turbine control systems and highlight recent industry trends and research in wind turbine control systems for grid integration and frequency stability.

Aho, J.; Buckspan, A.; Laks, J.; Fleming, P.; Jeong, Y.; Dunne, F.; Churchfield, M.; Pao, L.; Johnson, K.

2012-03-01T23:59:59.000Z

212

Tutorial of Wind Turbine Control for Supporting Grid Frequency through Active Power Control: Preprint  

SciTech Connect

As wind energy becomes a larger portion of the world's energy portfolio and wind turbines become larger and more expensive, wind turbine control systems play an ever more prominent role in the design and deployment of wind turbines. The goals of traditional wind turbine control systems are maximizing energy production while protecting the wind turbine components. As more wind generation is installed there is an increasing interest in wind turbines actively controlling their power output in order to meet power setpoints and to participate in frequency regulation for the utility grid. This capability will be beneficial for grid operators, as it seems possible that wind turbines can be more effective at providing some of these services than traditional power plants. Furthermore, establishing an ancillary market for such regulation can be beneficial for wind plant owner/operators and manufacturers that provide such services. In this tutorial paper we provide an overview of basic wind turbine control systems and highlight recent industry trends and research in wind turbine control systems for grid integration and frequency stability.

Aho, J.; Buckspan, A.; Laks, J.; Fleming, P.; Jeong, Y.; Dunne, F.; Churchfield, M.; Pao, L.; Johnson, K.

2012-03-01T23:59:59.000Z

213

EACLE: Energy-Aware Clustering Scheme with Transmission Power Control for Sensor Networks  

Science Conference Proceedings (OSTI)

In this paper, we propose a new energy efficient clustering scheme with transmission power control named "EACLE" (Energy-Aware CLustering scheme with transmission power control for sEnsor networks) for wireless sensor networks, which are composed of ... Keywords: clustering, energy efficiency, transmission power control, wireless sensor network

Kentaro Yanagihara; Jumpei Taketsugu; Kiyoshi Fukui; Shigeru Fukunaga; Shinsuke Hara; Ken-Ichi Kitayama

2007-02-01T23:59:59.000Z

214

Rotor power feedback control of wind turbine system doubly-fed induction generator  

Science Conference Proceedings (OSTI)

The paper deals with a new system of wind turbine active power vector control. The already familiar cascade regulation with internal vector component feedback of rotor current and external active and reactive power feedbacks control of wind turbine has ... Keywords: DFIG rotor power regulator, doubly-fed induction generator, simulation, vector control

J. Smajo

2006-09-01T23:59:59.000Z

215

Synchronization and power sharing for droop-controlled inverters in islanded microgrids  

Science Conference Proceedings (OSTI)

Motivated by the recent and growing interest in smart grid technology, we study the operation of DC/AC inverters in an inductive microgrid. We show that a network of loads and DC/AC inverters equipped with power-frequency droop controllers can be cast ... Keywords: Coupled oscillators, Distributed control, Inverters, Kuramoto model, Power-system control, Smart power applications, Synchronization

John W. Simpson-Porco, Florian DöRfler, Francesco Bullo

2013-09-01T23:59:59.000Z

216

Latency-sensitive power control for wireless ad-hoc networks  

Science Conference Proceedings (OSTI)

We investigate the impact of power control on latency in wireless ad-hoc networks. If transmission power is increased, interference increases, thus reducing network capacity. A node sending/relaying delay-sensitive real-time application traffic can, ... Keywords: ad-hoc networks, latency, medium access control, network connectivity, power control, wireless networks

Mohamed R. Fouad; Sonia Fahmy; Gopal Pandurangan

2005-10-01T23:59:59.000Z

217

Brief paper: Power-shaping control of reaction systems: The CSTR case  

Science Conference Proceedings (OSTI)

Power-shaping control is a recent approach for the control of nonlinear systems based on the physics of the dynamical system. It rests on the formulation of the dynamics in the Brayton-Moser form. One of the main obstacles for using the power-shaping ... Keywords: Brayton-Moser form, Non-isothermal CSTR, Nonlinear dynamical systems, Power-shaping control

A. Favache; D. Dochain

2010-11-01T23:59:59.000Z

218

Real Power and Reactive Power Control of a Three-Phase Single-Stage-PV System and PV voltage Stability  

Science Conference Proceedings (OSTI)

Grid-connected photovoltaic (PV) systems with power electronic interfaces can provide both real and reactive power to meet power system needs with appropriate control algorithms. This paper presents the control algorithm design for a three-phase single-stage grid-connected PV inverter to achieve either maximum power point tracking (MPPT) or a certain amount of real power injection, as well as the voltage/var control. The switching between MPPT control mode and a certain amount of real power control mode is automatic and seamless. Without the DC-to-DC booster stage, PV DC voltage stability is an important issue in the control design especially when the PV inverter is operating at maximum power point (MPP) with voltage/var control. The PV DC voltage collapse phenomenon and its reason are discussed. The method based on dynamic correction of the PV inverter output is proposed to ensure PV DC voltage stability. Simulation results of the single-stage PV system during system disturbances and fast solar irradiation changes confirm that the proposed control algorithm for single-stage PV inverters can provide appropriate real and reactive power services and ensure PV DC voltage stability during dynamic system operation and atmospheric conditions.

Li, Huijuan [ORNL; Xu, Yan [ORNL; Adhikari, Sarina [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Irminger, Philip [ORNL

2012-01-01T23:59:59.000Z

219

Asymptotics for Discrete Weighted Minimal Riesz Energy Problems on Rectifiable Sets  

E-Print Network (OSTI)

Given a compact $d$-rectifiable set $A$ embedded in Euclidean space and a distribution $\\rho(x)$ with respect to $d$-dimensional Hausdorff measure on $A$, we address the following question: how can one generate optimal configurations of $N$ points on $A$ that are "well-separated" and have asymptotic distribution $\\rho (x)$ as $N\\to \\infty$? For this purpose we investigate minimal weighted Riesz energy points, that is, points interacting via the weighted power law potential $V=w(x,y)|x-y|^{-s}$, where $s>0$ is a fixed parameter and $w$ is suitably chosen. In the unweighted case ($w\\equiv 1$) such points for $N$ fixed tend to the solution of the best-packing problem on $A$ as the parameter $s\\to \\infty$.

S. V. Borodachov; D. P. Hardin; E. B. Saff

2006-02-11T23:59:59.000Z

220

Low Power Control Techniques For TFT LCD Displays  

Science Conference Proceedings (OSTI)

Display power consumption is often the most significant contributor to the overall power budget for many portable devices. Traditionally, liquid crystal display (LCD) power minimization has focused on technology and circuit design. In this paper we take ...

Franco Gatti; Andrea Acquaviva; Luca Benini; Bruno Ricco'

2002-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Dynamic model of power system operation incorporating load control  

SciTech Connect

Load management has been proposed as a means whereby an electric utility can reduce its requirements for additional generation, transmission, and distribution investments, shift fuel dependency from limited to more abundant energy resources, and improve the efficiency of the electric energy system. There exist, however, serious technological and economic questions which must be answered to define the cost trade-offs between initiating a load management strategy or adding additional capacity to meet the load. One aspect of this complex problem is to determine how the load profile might be modified by the load management option being considered. Towards this end, a model has been developed to determine how a power system with an active load control system should be operated to make the best use of its available resources. The model is capable of handling all types of conventional generating sources including thermal, hydro, and pumped storage units, and most appliances being considered for direct control including those with inherent or designed storage characteristics. The model uses a dynamic programming technique to determine the optimal operating strategy for a given set of conditions. The use of the model is demonstrated. Case study results indicate that the production cost savings that can be achieved through the use of direct load control are highly dependent on utility characteristics, load characteristics, storage capacity, and penetration. The load characteristics that produce the greatest savings are: large storage capacity; high coincidence with the system peak; large connected load per point; and moderately high diversity fraction.

Kuliasha, M.A.

1980-10-01T23:59:59.000Z

222

Adaptive HVDC Control System and Power Oscillation Damping Methods: Theoretical Developments  

Science Conference Proceedings (OSTI)

This report demonstrates the basic principles behind supplementary control of high-voltage direct-current (HVDC) links for improving system dynamic performance, through case studies using DIgSILENT’s PowerFactory software. Power oscillation damping control through HVDC links is reported alongside adaptive control of HVDC power to ensure secure operation of power systems. Simulation results on a simple four-generator, two-area test system are presented, with a view to benchmark the results and ...

2012-12-12T23:59:59.000Z

223

Decentralized-coordinated model predictive control for a hydro-power valley  

Science Conference Proceedings (OSTI)

This paper aims at improving control systems for hydro-power production, by combining model predictive control techniques with decomposition-coordination methods for a global optimization over a whole hydro-power valley. It first recalls the model predictive ... Keywords: Case-study validation, Control optimization, Decomposition-coordination, Hydroelectricity, Model predictive control

J. ZáRate FlóRez, J. Martinez, G. BesançOn, D. Faille

2013-05-01T23:59:59.000Z

224

Decentralized optimal neuro-controllers for generation and transmission devices in an electric power network  

Science Conference Proceedings (OSTI)

In this paper, the dual heuristic programming (DHP) optimization algorithm is applied for the design of two LOCAL nonlinear optimal neuro-controllers on a practical multi-machine power system. One neuro-controller is designed to replace the conventional ... Keywords: Decentralized control, Dual heuristic programming, Optimal neuro-controller, Power network, Series capacitive reactance compensator

Jung-Wook Park; Ronald G. Harley; Ganesh K. Venayagamoorthy

2005-02-01T23:59:59.000Z

225

Damping of low frequency oscillations in power system network using swarm intelligence tuned fuzzy controller  

Science Conference Proceedings (OSTI)

In this paper, a particle swarm intelligent optimisation based optimal fuzzy scheme has been developed to design intelligent adaptive controllers for improving the dynamic and transient stability performance of multimachine power system. This concept ... Keywords: PSO, PSS, adaptive control, dynamic stability, fuzzy control, intelligent control, low frequency oscillations, neural networks, neuro-fuzzy logic, particle swarm optimisation, power system stabiliser

N. Albert Singh; K. A. Muraleedharan; K. Gomathy

2010-12-01T23:59:59.000Z

226

Constrained model predictive control implementation for a heavy-duty gas turbine power plant  

Science Conference Proceedings (OSTI)

In this paper, model predictive control (MPC) strategy is implemented to a GE9001E gas turbine power plant. A linear model is developed for the gas turbine using conventional mathematical models and ARX identification procedure. Also a process control ... Keywords: ARX, PID, gas turbine, identification, modeling, multivariable control, power plant, predictive control

Hadi Ghorbani; Ali Ghaffari; Mehdi Rahnama

2008-06-01T23:59:59.000Z

227

Evaluation of MerCAP for Power Plant Mercury Control  

SciTech Connect

This report is submitted to the U.S. Department of Energy National Energy Technology Laboratory (DOE-NETL) as part of Cooperative Agreement DE-FC26-03NT41993, 'Evaluation of EPRI's MerCAP{trademark} Technology for Power Plant Mercury Control'. This project has investigated the mercury removal performance of EPRI's Mercury Capture by Amalgamation Process (MerCAP{trademark}) technology. Test programs were conducted to evaluate gold-based MerCAP{trademark} at Great River Energy's Stanton Station Unit 10 (Site 1), which fired both North Dakota lignite (NDL) and Power River Basin (PRB) coal during the testing period, and at Georgia Power's Plant Yates Unit 1 (Site 2) [Georgia Power is a subsidiary of The Southern Company] which fires a low sulfur Eastern bituminous coal. Additional tests were carried out at Alabama Power's Plant Miller, which fires Powder River Basin Coal, to evaluate a carbon-based MerCAP{trademark} process for removing mercury from flue gas downstream of an electrostatic precipitator [Alabama Power is a subsidiary of The Southern Company]. A full-scale gold-based sorbent array was installed in the clean-air plenum of a single baghouse compartment at GRE's Stanton Station Unit 10, thereby treating 1/10th of the unit's exhaust gas flow. The substrates that were installed were electroplated gold screens oriented parallel to the flue gas flow. The sorbent array was initially installed in late August of 2004, operating continuously until its removal in July 2006, after nearly 23 months. The initial 4 months of operation were conducted while the host unit was burning North Dakota lignite (NDL). In November 2004, the host unit switched fuel to burn Powder River Basin (PRB) subbituminous coal and continued to burn the PRB fuel for the final 19 months of this program. Tests were conducted at Site 1 to evaluate the impacts of flue gas flow rate, sorbent plate spacing, sorbent pre-cleaning and regeneration, and spray dryer operation on MerCAP{trademark} performance. At Site 2, a pilot-scale array was installed in a horizontal reactor chamber designed to treat approximately 2800 acfm of flue gas obtained from downstream of the plant's flue gas desulfurization (FGD) system. The initial MerCAP{trademark} array was installed at Plant Yates in January 2004, operating continuously for several weeks before a catastrophic system failure resulting from a failed flue gas fan. A second MerCAP{trademark} array was installed in July 2006 and operated for one month before being shut down for a reasons pertaining to system performance and host site scheduling. A longer-term continuous-operation test was then conducted during the summer and fall of 2007. Tests were conducted to evaluate the impacts of flue gas flow rate, sorbent space velocity, and sorbent rinsing frequency on mercury removal performance. Detailed characterization of treated sorbent plates was carried out in an attempt to understand the nature of reactions leading to excessive corrosion of the substrate surfaces.

Carl Richardson

2008-09-30T23:59:59.000Z

228

Controlling mercury emissions from coal-fired power plants  

Science Conference Proceedings (OSTI)

Increasingly stringent US federal and state limits on mercury emissions form coal-fired power plants demand optimal mercury control technologies. This article summarises the successful removal of mercury emissions achieved with activated carbon injection and boiler bromide addition, technologies nearing commercial readiness, as well as several novel control concepts currently under development. It also discusses some of the issues standing in the way of confident performance and cost predictions. In testing conducted on western coal-fired units with fabric filters or TOXECON to date, ACI has generally achieved mercury removal rates > 90%. At units with ESPs, similar performance requires brominated ACI. Alternatively, units firing western coals can use boiler bromide addition to increase flue gas mercury oxidation and downstream capture in a wet scrubber, or to enhance mercury removal by ACI. At eastern bituminous fired units with ESPs, ACI is not as effective, largely due to SO{sub 3} resulting from the high sulfur content of the coal or the use of SO{sub 3} flue gas conditioning to improve ESP performance. 7 refs., 3 figs.

Chang, R. [Electric Power Research Institute, Palo Alto, CA (United States)

2009-07-15T23:59:59.000Z

229

Interline Photovoltaic (I-PV) power system - A novel concept of power flow control and management  

E-Print Network (OSTI)

This paper presents a new system configuration for a large-scale Photovoltaic (PV) power system with multi-line transmission/distribution networks. A PV power plant is reconfigured in a way that two adjacent power system ...

Khadkikar, Vinod

230

Grid-Connected Marine Current Generation System Power Smoothing Control Using Supercapacitors  

E-Print Network (OSTI)

Grid-Connected Marine Current Generation System Power Smoothing Control Using Supercapacitors to reduce the fluctuation of generator power. In the second step, Supercapacitor (SC) Energy Storage System fluctuation, swell effect, power smoothing control, supercapacitor. I. [NTRODUCTION [n the recent years

Paris-Sud XI, Université de

231

Improving monitoring, control and protection of power grid using wide area synchro-phasor measurements  

Science Conference Proceedings (OSTI)

When disturbances occur in power grid, monitoring, control and protection systems are required to stop the grid degradation, restore it to a normal state, and hence minimize their effects. However, in wide area power grid resulting from large extension ... Keywords: emergency control and optimization systems, phasor measurement units, power system, wide area protection system

Hamid Bentarzi

2010-05-01T23:59:59.000Z

232

Fuzzy Logic Controller for Enhancement of Transient Stability in Multi Machine AC-DC Power Systems  

Science Conference Proceedings (OSTI)

This paper discusses the impact of HVDC on Power System Stability and proposes a new type of control mechanism based on Fuzzy set theory to augment dynamic performance of a multi-machine power system. To have good damping characteristics over a wide ... Keywords: HVDC, Power System Stability, Multi-Machine Stability, Fuzzy Logic Controller

M. Uma Vani; P. V. Ramana Rao

2010-11-01T23:59:59.000Z

233

Predictive Power Control of Doubly-Fed Induction Generator for Wave Energy Converters  

E-Print Network (OSTI)

the Doubly- fed induction generator (DFIG). This paper deals then with a model-based predictive power control of a DFIG-based Wave Energy Converter (WEC). In the proposed control approach, the predicted output power was calculated using a DFIG linearized state-space model. The DFIG-based WEC power tracking performances further

Paris-Sud XI, Université de

234

Var Coordinated Control of DFIG Impact on Small Signal Stability of Power System  

Science Conference Proceedings (OSTI)

The wind farm based on Doubly Fed Induction Generator (DFIG) is built. Not only it can be as active power source to provide active power to network, but also as reactive power source to stabilize voltage or supply Var compensation (reactive power absorbed ... Keywords: Doubly Fed Induction Generator, Var coordinated control, low-frequency oscillation, small signal stability

Lei Wang; Hongjie Jia

2012-04-01T23:59:59.000Z

235

Controlling Power Plant CO2 Emissions: A Long-Range View  

NLE Websites -- All DOE Office Websites (Extended Search)

CONTROLLING POWER PLANT CO CONTROLLING POWER PLANT CO 2 EMISSIONS: A LONG RANGE VIEW John Marion (john.l.marion@power.alstom.com; 860-285-4539) Nsakala ya Nsakala (nsakala.y.nsakala@power.alstom.com; 860-285-2018) ALSTOM Power Plant Laboratories 2000 Day Hill Road Windsor, CT 06095, USA Timothy Griffin (timothy.griffin@power.alstom.com; +41 56/486 82 43) Alain Bill (alain.bill@power.alstom.com; +41 56/486 81 07) ALSTOM Power Technology Center 5405 Baden-Daettwil, Switzerland ABSTRACT ALSTOM Power (ALSTOM) is an international supplier of power generation with concern for the environment. We are aware of the present scientific concerns regarding greenhouse gas emissions and the role of fossil fuel use for power generation. Although the scientific and policy dialogue on global climate change is far from conclusive, ALSTOM continues to

236

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

The work described in this report was funded by the Federal Energy Regulatory Commission, Office of Electric Reliability through a subcontract administered by the Lawrence Berkeley National Laboratory, which is operated by the University of California for the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Disclaimer This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor The Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or The Regents of the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. Power and Frequency Control as it Relates to Wind-Powered Generation

Ernest Orlando Lawrence; John Undrill; John Undrill Llc; John Undrill; John Undrill Llc

2010-01-01T23:59:59.000Z

237

Power electronics system modeling and simulation  

SciTech Connect

This paper introduces control system design based softwares, SIMNON and MATLAB/SIMULINK, for power electronics system simulation. A complete power electronics system typically consists of a rectifier bridge along with its smoothing capacitor, an inverter, and a motor. The system components, featuring discrete or continuous, linear or nonlinear, are modeled in mathematical equations. Inverter control methods,such as pulse-width-modulation and hysteresis current control, are expressed in either computer algorithms or digital circuits. After describing component models and control methods, computer programs are then developed for complete systems simulation. Simulation results are mainly used for studying system performances, such as input and output current harmonics, torque ripples, and speed responses. Key computer programs and simulation results are demonstrated for educational purposes.

Lai, Jih-Sheng

1994-12-31T23:59:59.000Z

238

Optimal control for maximum power in thermal and chemical systems  

Science Conference Proceedings (OSTI)

This research treats power optimization for energy converters, such like thermal, solar and chemical engines. Thermodynamic analyses lead to converter's efficiency and limiting power. Steady and dynamic systems are investigated. Static optimization of ...

Stanislaw Sieniutycz

2009-09-01T23:59:59.000Z

239

Hybrid Power System with a Controlled Energy Storage: Preprint  

DOE Green Energy (OSTI)

We investigated a small isolated hybrid power system that used two types of power generation; wind turbine and diesel generation. The interaction of diesel generation, the wind turbine, and the local load is complicated because both the load and the wind turbine fluctuate during the day. These fluctuations create imbalances in power distribution (energy sources are not equal to energy sinks) that can affect the frequency and the voltage in the power system. The addition of energy storage will help balance the distribution of power in the power network. For this paper, we studied the interaction among hybrid power system components and the relative size of the components. We also show how the contribution of wind energy affects the entire power system and distribution and the role of energy storage under the transient conditions caused by load changes and wind turbine start ups.

Muljadi, E.; Bialasiewicz, J. T.

2003-11-01T23:59:59.000Z

240

Multi-agent control and operation of electric power distribution systems  

Science Conference Proceedings (OSTI)

This dissertation presents operation and control strategies for electric power distribution systems containing distributed generators. First, models of microturbines and fuel cells are developed. These dynamic models are incorporated in a power system ...

Amer Al-Hinai / Ali Feliachi

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Modelling and decentralised runtime control of self-stabilising power micro grids  

Science Conference Proceedings (OSTI)

Electric power production infrastructures around the globe are shifting from centralised, controllable production to decentralised structures based on distributed microgeneration. As the share of renewable energy sources such as wind and solar power ...

Arnd Hartmanns; Holger Hermanns

2012-10-01T23:59:59.000Z

242

Evaluation of MerCAP^TM for Power Plant Mercury Control  

NLE Websites -- All DOE Office Websites (Extended Search)

Evaluation of MErCaP(tm) for PowEr Plant MErCury Control Background Several technologies are under development for removing mercury from power plant flue gas streams. The mercury...

243

Sleep Control for Base Stations Powered by Heterogeneous Energy Sources  

E-Print Network (OSTI)

makes it hard to utilize renewable energy efficiently. In literature, some efforts have been made to the power grid, some BSs are purely powered by the renewable energy. BS sleep is introduced not only to save grid power, but also to store renewable energy for future use when the temporal traffic variation does

244

POWER BALANCING CONTROL WITH LARGE SCALE WIND POWER INTEGRATION IN DENMARK  

E-Print Network (OSTI)

kV transmission system with the HVDC connections to Nordel systems (Norway and Sweden) in the north power exchange. Earlier studies in [4] have shown that the power exchange through the HVDC links plants and the power exchange via the HVDC connections. The overall model includes the power gradient

Bak-Jensen, Birgitte

245

Study on Reactive Power and Voltage Control of Power Grid with Small Hydropower  

Science Conference Proceedings (OSTI)

When it is in the wet season and the load is low, reactive power surplus and voltage rise are caused by high-efficiency power generation of small hydropower and load reduction in Linjiang region, Baishan city, JiLin province. These problems, which exist ... Keywords: small hydro power, vally load, reactive power balance, the rise in voltage, generator in leading power factor on operation

Yaopeng Bai; Lijie Xu; Wei Wang

2010-06-01T23:59:59.000Z

246

Identification and control of power plant de-superheater using soft computing techniques  

Science Conference Proceedings (OSTI)

Tight turbine steam temperature control is a necessity for obtaining long lifetime, high efficiency, high load following capability and high availability in power plants. The present work reports a systematic approach for the control strategy design ... Keywords: Fuzzy systems, Genetic algorithms, Industrial power systems, Neuro-fuzzy identification, Temperature control

Ali Ghaffari; Ali Reza Mehrabian; Morteza Mohammad-Zaheri

2007-03-01T23:59:59.000Z

247

Power control schemes in wireless sensor networks for homecare e-health applications  

Science Conference Proceedings (OSTI)

Power control is an important research topic for ad-hoc Wireless Sensor Networks (WSNs). In today's sophisticated and competitive wireless environment, the control of the energy consumption in a WSN for homecare e-health makes it possible to guarantee ... Keywords: homecare e-health, low-energy consumption, power control, wireless sensor networks

Nikolaos A. Pantazis; Dimitrios D. Vergados; Nikolaos I. Miridakis; Dimitrios J. Vergados

2008-07-01T23:59:59.000Z

248

PERFORMANCE ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL  

E-Print Network (OSTI)

PERFORMANCE ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL D.J.Leith W Power regulation of horizontal-axis grid-connected up-wind constant-speed pitch-regulated wind turbines, switched linear control is more suited for application to wind turbines than the nonlinear control strategy

Duffy, Ken

249

Instantaneous Active and Nonactive Power Control of Distributed Energy Resources with Current Limiter  

SciTech Connect

Abstract -- Distributed energy resources (DER) with a power electronics inverter interface can provide both active power and nonactive power simultaneously and independently. A decoupled control algorithm of active power and nonactive power is developed based on the instantaneous active power and nonactive power theory. A current limiter is combined to the control algorithm, and it ensures that the inverter is not overloaded. During the normal system operation, the active power has higher priority over the nonactive power so that the energy from a DER can be fully transferred to the grid. Within the inverter s capability, nonactive power is provided to the grid as required. With this control algorithm, the inverter s capabilities are taken full advantage at all times, both in terms of functionality as well as making use of its full KVA rating. Through the algorithm, the inverter s active power and nonactive power are controlled directly, simultaneously, and independently. Several experimental results fully demonstrate the validity and effectiveness of this new control algorithm. As evidenced by the fast dynamic response that results, a DER system with the control algorithm can provide full services to the grid in both steady state and during transient events.

Xu, Yan [ORNL; Li, Huijuan [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Kueck, John D [ORNL

2010-01-01T23:59:59.000Z

250

Solar power system requiring no active control device  

SciTech Connect

A solar power system has a photovoltaic array having a locus of peak power points for various insolation levels, a voltage-dependent variable resistance load such as a water electrolysis unit electrically connected to the array, and a demand-dependent variable resistance load such as a dc to ac inverter connected in parallel with the electrolysis unit. The electrolysis unit or other voltage-dependent variable resistance load has a voltage-current characteristic in which the operating point is displaced from the array's peak power point for most insolation levels. The characteristic is displaced towards higher voltage-lower current operating points. The inverter may move the operating point of the photovoltaic array toward its peak power point when the load requires power. The system may be designed so that the array operates within about 5 percent of its peak power point over a wide range of inverter power demands. A fuel cell may be connected in parallel with the array to provide power to the inverter at low insolation levels, at night or in low sunlight. The fuel cell may use the hydrogen produced by the electrolysis unit for fuel. The total photovoltaic power made available by the system of this invention is generally greater than 95 percent and often greater than 98 percent of the maximum power which the photovoltaic array may produce for many insolation levels.

Tison, R.R.

1982-07-27T23:59:59.000Z

251

Gas turbine control and load sharing of a shipboard power system.  

E-Print Network (OSTI)

??The objective of this research is to design a controller for a gas turbine of an ElectricShipboard Power System (ESPS) and to develop a load… (more)

Fernandes, Anisha M. C., 1980-

2006-01-01T23:59:59.000Z

252

Techniques for Battery Health Conscious Power Management via Electrochemical Modeling and Optimal Control.  

E-Print Network (OSTI)

??This dissertation combines electrochemical battery models and optimal control theory to study power management in energy storage/conversion systems. This topic is motivated by the need… (more)

Moura, Scott J.

2011-01-01T23:59:59.000Z

253

A Generalized Inverter Control Method for a Variable Speed Wind Power System Under Unbalanced Operting Conditions.  

E-Print Network (OSTI)

??This thesis presents a generalized control method for complete harmonic elimination and adjustable power factor of a grid side inverter under unbalanced operating conditions used… (more)

Wu, Shuang

2010-01-01T23:59:59.000Z

254

Modeling and control coordination of power systems with FACTS devices in steady-state operating mode.  

E-Print Network (OSTI)

??This thesis is devoted to the development of new models for a recently-implemented FACTS (flexible alternating current transmission system) device, the unified power flow controller… (more)

Nguyen, Van Liem

2008-01-01T23:59:59.000Z

255

REAL TIME TEST BED DEVELOPMENT FOR POWER SYSTEM OPERATION,CONTROL AND CYBERSECURITY.  

E-Print Network (OSTI)

?? The operation and control of the power system in an efficient way is important in order to keep the system secure, reliable and economical.… (more)

Reddi, Ram Mohan

2010-01-01T23:59:59.000Z

256

Multi-agent control and operation of electric power distribution systems.  

E-Print Network (OSTI)

??This dissertation presents operation and control strategies for electric power distribution systems containing distributed generators. First, models of microturbines and fuel cells are developed. These… (more)

Al-Hinai, Amer.

2005-01-01T23:59:59.000Z

257

Assessment of Thermal Control Technologies for Cooling Electric Vehicle Power Electronics  

DOE Green Energy (OSTI)

NREL is assessing thermal control technologies to improve the thermal performance of power electronics devices for electric vehicles, while reducing the cost, weight, and volume of the system.

Kelly, K.; Abraham, T.; Bennion, K.; Bharathan, D.; Narumanchi, S.; O'Keefe, M.

2008-01-01T23:59:59.000Z

258

Power control architectures for cold cathode fluorescent lamp and light emitting diode based light sources.  

E-Print Network (OSTI)

?? In this dissertation, two different energy efficient power supply topologies are introduced for controlling cold cathode fluorescent lamp (CCFL) and high-brightness light emitting diode… (more)

Doshi, Montu V.

2010-01-01T23:59:59.000Z

259

Magnetically Controlled Reactor Shrinks Power Quality Costs and...  

NLE Websites -- All DOE Office Websites (Extended Search)

ensures less than 2-3% main harmonic distortion even without special filters. Transformer-like construction ensures reliable operation. MCR's increase power quality through...

260

Virtual Power Plant Simulation and Control Scheme Design.  

E-Print Network (OSTI)

?? Virtual Power Plant (VPP) is a concept that aggregate Distributed Energy Resources (DER) together, aims to overcome the capacity limits of single DER and… (more)

Chen, Zhenwei

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Lillgrund Wind Farm Modelling and Reactive Power Control.  

E-Print Network (OSTI)

?? The installation of wind power plant has significantly increased since several years due to the recent necessity of creating renewable and clean energy sources.… (more)

Boulanger, Isabelle

2009-01-01T23:59:59.000Z

262

Low-Power Maximum Power Point Tracker with Digital Control for Thermophotovoltaic Generators  

E-Print Network (OSTI)

This paper describes the design, optimization, and evaluation of the power electronics circuitry for a low-power portable thermophotovotaic (TPV) generator system. TPV system is based on a silicon micro-reactor design and ...

Pilawa, Robert

263

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

turbine power if the wind is favorable at the moment and response provided by borrowing energy from the rotors

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

264

Advanced Underground Vehicle Power and Control Fuelcell Mine Locomotive  

E-Print Network (OSTI)

-- Tethered -- Diesel -- Battery · Solution by fuelcells will provide cost offsets -- Lower recurring costs -- Higher availability -- Lower ventilation costs A PROBLEM AND OPPORTUNITY Underground Traction Power #12 available battery-powered 4-ton locomotive · Remove traction battery module and use existing electric drive

265

Optimal Sliding Mode Gaussian Control of Hydro Power Plants.  

E-Print Network (OSTI)

??This thesis presents a study of a hydroelectric plant under different control strategies for load frequency control. Both isolated systems and systems connected to a… (more)

Rittenhouse, Benjamin

2013-01-01T23:59:59.000Z

266

Experience curves for power plant emission control technologies  

E-Print Network (OSTI)

Selective Catalytic Reduction (SCR) NOx Control, Prepared byReduction (SCR) Technology for the Control of Nitrogen Oxide (NOx)NOx removal technologies. Volume 1. Selective catalytic reduction.

Rubin, Edward S.; Yeh, Sonia; Hounshell, David A

2007-01-01T23:59:59.000Z

267

A Two-Stage Distributed Architecture for Voltage Control in Power Distribution Systems  

E-Print Network (OSTI)

-positive power injections. With respect to this, the University of Illinois solar decathlon house--the Gable Home by the US DOE Smart Grid initiative, and its European counterpart Electricity Networks of the Future, power1 A Two-Stage Distributed Architecture for Voltage Control in Power Distribution Systems Brett A

Hadjicostis, Christoforos

268

EPRI Power Electronics-Based Transmission Controllers Reference Book ("The Gold Book")  

Science Conference Proceedings (OSTI)

EPRI is sponsoring development of a first edition of the EPRI Power Electronics-Based Transmission Controllers Reference Book. This report is the most recent draft of a chapter for the "Gold Book," an authoritative guide for utilities and others who install and maintain power electronics equipment to increase power transfer capability.

2009-12-23T23:59:59.000Z

269

Utility-Scale Power Router: Dynamic Control of Grid Assets Using Direct AC Converter Cells  

SciTech Connect

ADEPT Project: Georgia Tech is developing a cost-effective, utility-scale power router that uses an enhanced transformer to more efficiently direct power on the grid. Existing power routing technologies are too expensive for widespread use, but the ability to route grid power to match real-time demand and power outages would significantly reduce energy costs for utilities, municipalities, and consumers. Georgia Tech is adding a power converter to an existing grid transformer to better control power flows at about 1/10th the cost of existing power routing solutions. Transformers convert the high-voltage electricity that is transmitted through the grid into the low-voltage electricity that is used by homes and businesses. The added converter uses fewer steps to convert some types of power and eliminates unnecessary power storage, among other improvements. The enhanced transformer is more efficient, and it would still work even if the converter fails, ensuring grid reliability.

None

2010-09-01T23:59:59.000Z

270

Advanced regulatory control and coordinated plant-wide control strategies for IGCC targeted towards improving power ramp-rates  

Science Conference Proceedings (OSTI)

As part of ongoing R&D activities at the National Energy Technology Laboratory's (NETL) Advanced Virtual Energy Simulation Training & Research (AVESTAR™) Center, this paper highlights strategies for enhancing low-level regulatory control and system-wide coordinated control strategies implemented in a high-fidelity dynamic simulator for an Integrated Gasification Combined Cycle (IGCC) power plant with carbon capture. The underlying IGCC plant dynamic model contains 20 major process areas, each of which is tightly integrated with the rest of the power plant, making individual functionally-independent processes prone to routine disturbances. Single-loop feedback control although adequate to meet the primary control objective for most processes, does not take into account in advance the effect of these disturbances, making the entire power plant undergo large offshoots and/or oscillations before the feedback action has an opportunity to impact control performance. In this paper, controller enhancements ranging from retuning feedback control loops, multiplicative feed-forward control and other control techniques such as split-range control, feedback trim and dynamic compensation, applicable on various subsections of the integrated IGCC plant, have been highlighted and improvements in control responses have been given. Compared to using classical feedback-based control structure, the enhanced IGCC regulatory control architecture reduces plant settling time and peak offshoots, achieves faster disturbance rejection, and promotes higher power ramp-rates. In addition, improvements in IGCC coordinated plant-wide control strategies for “Gasifier-Lead”, “GT-Lead” and “Plantwide” operation modes have been proposed and their responses compared. The paper is concluded with a brief discussion on the potential IGCC controller improvements resulting from using advanced process control, including model predictive control (MPC), as a supervisory control layer.

Mahapatra, P.; Zitney, S.

2012-01-01T23:59:59.000Z

271

Control strategies for supercritical carbon dioxide power conversion systems  

E-Print Network (OSTI)

The supercritical carbon dioxide (S-C02) recompression cycle is a promising advanced power conversion cycle which couples well to numerous advanced nuclear reactor designs. This thesis investigates the dynamic simulation ...

Carstens, Nathan, 1978-

2007-01-01T23:59:59.000Z

272

Experience curves for power plant emission control technologies  

E-Print Network (OSTI)

and nitrogen oxides (NO x ) from coal-fired electric powerReferences Soud, H.N. (1994) FGD Installations on Coal-FiredPlants, IEA Coal Research, London. Soud, H. (2001) Personal

Rubin, Edward S.; Yeh, Sonia; Hounshell, David A

2007-01-01T23:59:59.000Z

273

Design of control for efficiency of AUV power systems  

E-Print Network (OSTI)

The MIT Rapid Development Group designed and built an internal combustion hybrid recharging system for the REMUS 600 Autonomous Underwater Vehicle (AUV) in collaboration with the MIT Lincoln Laboratory. This power system ...

Ware, Laura M. (Laura Marie)

2012-01-01T23:59:59.000Z

274

Energy 32 (2007) 406417 Modeling and control of a SOFC-GT-based autonomous power system  

E-Print Network (OSTI)

Energy 32 (2007) 406­417 Modeling and control of a SOFC-GT-based autonomous power system Rambabu In this article, a dynamic, lumped model of a solid oxide fuel cell (SOFC) is described, as a step towards developing control relevant models for a SOFC combined with a gas turbine (GT) in an autonomous power system

Foss, Bjarne A.

275

A Local Model Networks Based Multivariable Long-Range Predictive Control Strategy for Thermal Power Plants  

Science Conference Proceedings (OSTI)

Load-cycling operation of thermal power plants leads to changes in operating point right across the whole operating range. This results in non-linear variations in most of the plant variables. This paper investigates methods to account for non-linearities ... Keywords: Constrained multivariable control, local model networks, long range predictive control, thermal power plant boiler

G. PRASAD; E. SWIDENBANK; B. W. HOGG

1998-10-01T23:59:59.000Z

276

Extreme learning machine based wind speed estimation and sensorless control for wind turbine power generation system  

Science Conference Proceedings (OSTI)

This paper proposes a precise real-time wind speed estimation method and sensorless control for variable-speed variable-pitch wind turbine power generation system (WTPGS). The wind speed estimation is realized by a nonlinear input-output mapping extreme ... Keywords: Extreme learning machine, Sensorless control, Wind speed estimation, Wind turbine power generation system

Si Wu; Youyi Wang; Shijie Cheng

2013-02-01T23:59:59.000Z

277

Nonlinear predictive control to track deviated power of an identified NNARX model of a hydro plant  

Science Conference Proceedings (OSTI)

This paper presents the performance study of predictive control approach in application to hydro plant. The tracking on deviated power as reference signal for identified neural network nonlinear autoregressive with exogenous signal (NNARX) hydro plant ... Keywords: Deviated power, Hydro plant, Identification, Predictive control, Random load

Nand Kishor

2008-11-01T23:59:59.000Z

278

Synchronization and Power Sharing for Droop-Controlled Inverters in Islanded Microgrids  

E-Print Network (OSTI)

Synchronization and Power Sharing for Droop-Controlled Inverters in Islanded Microgrids John W in an inductive microgrid. We show that a network of loads and DC/AC inverters equipped with power-frequency droop model, distributed control. 1 Introduction A microgrid is a low-voltage electrical network, hetero

Bullo, Francesco

279

Engineering quality control of solar-powered intelligent water-saving irrigation  

Science Conference Proceedings (OSTI)

The development tendency of the agricultural irrigation technology is Automatic water-saving irrigation, powered by solar energy and achieved control purposes by moisture content monitoring techniques and the variable irrigation technology. In this paper, ... Keywords: intelligent, quality control, solar power, water-saving irrigation

Liu Xiaochu; Wu Hualong; Ling Jingpeng; Tao Jianhua; Yao Li

2010-03-01T23:59:59.000Z

280

Joint optimisation for power control, scheduling and routing algorithms in the infrastructure wireless mesh network  

Science Conference Proceedings (OSTI)

The performance optimisation model for the IEEE 802.16 standard based wireless mesh network is presented and a joint optimisation method is proposed as the sub-optimal solution strategy, in which the power control, scheduling and routing algorithms ... Keywords: IEEE 80216, WMN, network throughput, performance optimisation, power control, routing, scheduling, simulation, wireless mesh networks, wireless networks

Mugen Peng; Yingjie Wang; Kun Wang; Wenbo Wang

2008-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Neutral Beam Power System for TPX  

SciTech Connect

The Tokamak Physics Experiment (TPX) will utilize to the maximum extent the existing Tokamak Fusion Test Reactor (TFTR) equipment and facilities. This is particularly true for the TFTR Neutral Beam (NB) system. Most of the NB hardware, plant facilities, auxiliary sub-systems, power systems, service infrastructure, and control systems can be used as is. The major changes in the NB hardware are driven by the new operating duty cycle. The TFTR Neutral Beam was designed for operation of the Sources for 2 seconds every 150 seconds. The TPX requires operation for 1000 seconds every 4500 seconds. During the Conceptual Design Phase of TPX every component of the TFTR NB Electrical Power System was analyzed to verify whether the equipment can meet the new operational requirements with our without modifications. The Power System converts 13.8 kV prime power to controlled pulsed power required at the NB sources. The major equipment involved are circuit breakers, auto and rectifier transformers surge suppression components, power tetrodes, HV Decks, and HVDC power transmission to sources. Thermal models were developed for the power transformers to simulate the new operational requirements. Heat runs were conducted for the power tetrodes to verify capability. Other components were analyzed to verify their thermal limitations. This paper describes the details of the evaluation and redesign of the electrical power system components to meet the TPX operational requirements.

Ramakrishnan, S.; Bowen, O.N.; O`Conner, T.; Edwards, J.; Fromm, N.; Hatcher, R.; Newman, R.; Rossi, G.; Stevenson, T.; von Halle, A.

1993-11-01T23:59:59.000Z

282

Pre-validation of nuclear power plant control room design  

Science Conference Proceedings (OSTI)

Evaluation of the design of complex automation and control room systems is an essential phase in the design process in the nuclear field. For example, in order to meet the nuclear regulatory requirements, the new control room systems have to be evaluated ... Keywords: concept of operations, control room, pre-validation, verification & validation

Jari Laarni; Paula Savioja; Hannu Karvonen; Leena Norros

2011-07-01T23:59:59.000Z

283

Testing Active Power Control from Wind Power at the National Wind Technology Center (NWTC) (Presentation)  

DOE Green Energy (OSTI)

In order to keep the electricity grid stable and the lights on, the power system relies on certain responses from its generating fleet. This presentation evaluates the potential for wind turbines and wind power plants to provide these services and assist the grid during critical times.

Ela, E.

2011-05-01T23:59:59.000Z

284

Energy Saving by Limiting Standby Power Loss and Using Smart Power Control  

Science Conference Proceedings (OSTI)

Now-a-days efficient energy management has become very crucial. Fossil fuel is exhaustible and its use is discouraged because of its adverse effect on climate change, Nuclear power is also not suitable because of safety and security concerns, on the ... Keywords: energy saving, standby power, LDR, SSR, LM35, MCU, GSM

S. M. Masudur Rahman Al-Arif; Kazi Mahatb Kadir; Md. Adnan Morshed; A. H. M. Iftekharul Ferdous; Md. Mahabubul Alam; Md. Shahidul Haque

2011-11-01T23:59:59.000Z

285

Robust Controller Design for Simultaneous Control of Throttle Pressure and Megawatt Output in a Power Plant Unit  

Science Conference Proceedings (OSTI)

Recently proposed (( and (-synthesis controller design methodologies permit the design of high-performance control systems for plants that are difficult to model accurately. The work summarized in this report assesses the benefits of the (( and (-synthesis controllers for the simultaneous control of throttle pressure and megawatt output in a power plant unit, while also serving to clarify the (( and (-synthesis design methods by an example.

1999-02-25T23:59:59.000Z

286

Distributed control for optimal reactive power compensation in smart microgrids  

E-Print Network (OSTI)

We consider the problem of optimal reactive power compensation for the minimization of power distribution losses in a smart microgrid. We first propose an approximate model for the power distribution network, which allows us to cast the problem into the class of convex quadratic, linearly constrained, optimization problems. We also show how this model provides the tools for a distributed approach, in which agents have a partial knowledge of the problem parameters and state, and can only perform local measurements. Then, we design a randomized, gossip-like optimization algorithm, providing conditions for convergence together with an analytic characterization of the convergence speed. The analysis shows that the best performance can be achieved when we command cooperation among agents that are neighbors in the smart microgrid topology. Numerical simulations are included to validate the proposed model and to confirm the analytic results about the performance of the proposed algorithm.

Bolognani, Saverio

2011-01-01T23:59:59.000Z

287

Analysis and synthesis of HVDC controls for robust stability of power systems  

Science Conference Proceedings (OSTI)

High Voltage DC (HVDC) links have controllable characteristics with potential for affecting system stability. This paper follows the robustness methodology procedure to analyze the stability robustness of HVDC controls in power systems over a range of operating conditions. A novel method to design power system controllers using the robustness methodology is also proposed. Numerical results for a sample test-system are obtained and compared with those obtained by conventional techniques.

Venkataraman, S.; Khammash, M.H.; Vittal, V. [Iowa State Univ., Ames, IA (United States). Dept. of Electrical Engineering and Computer Engineering

1995-11-01T23:59:59.000Z

288

Rectified Wind Forcing and Latent Heat Flux Produced by the Madden–Julian Oscillation  

Science Conference Proceedings (OSTI)

Rectification of (Madden–Julian oscillation) MJO-induced wind speed and latent heat flux variations across the tropical Indian and western Pacific Oceans is estimated using 51 yr of NCEP–NCAR reanalysis. The rectified wind speed anomaly is ...

Toshiaki Shinoda; Harry H. Hendon

2002-12-01T23:59:59.000Z

289

Automated Monitoring Functions for Improved Power System Operation and Control  

E-Print Network (OSTI)

analysis of data collected in substations of an electric power system. The new functions are first defined and architecture of the integrated substation application is proposed. Database and user interfacing needs are also benefits to be drawn from the concept of substation data integration and information exchange. I

Kezunovic, Mladen

290

Automated monitoring functions for improved power system operation and control  

E-Print Network (OSTI)

collected in substations of an electric power system can be developed. The new functions are first defined and architecture of the integrated substation solution is proposed. Database and user interfacing needs are also benefits to be drawn from the concept of substation data integration and information exchange. I

291

Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module  

SciTech Connect

The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage.

Pitel, Ira J. (Whippany, NJ)

1987-02-03T23:59:59.000Z

292

Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module  

SciTech Connect

The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage. 19 figs.

Pitel, I.J.

1987-02-03T23:59:59.000Z

293

Load controller and method to enhance effective capacity of a photovoltaic power supply  

DOE Patents (OSTI)

A load controller and method are provided for maximizing effective capacity of a non-controllable, renewable power supply coupled to a variable electrical load also coupled to a conventional power grid. Effective capacity is enhanced by monitoring power output of the renewable supply and loading, and comparing the loading against the power output and a load adjustment threshold determined from an expected peak loading. A value for a load adjustment parameter is calculated by subtracting the renewable supply output and the load adjustment parameter from the current load. This value is then employed to control the variable load in an amount proportional to the value of the load control parameter when the parameter is within a predefined range. By so controlling the load, the effective capacity of the non-controllable, renewable power supply is increased without any attempt at operational feedback control of the renewable supply. The renewable supply may comprise, for example, a photovoltaic power supply or a wind-based power supply.

Perez, Richard (Delmar, NY)

2000-01-01T23:59:59.000Z

294

Journey to Flexible, Reliable, Laboratory Platform for Simultaneous Control of Multiple Reactive Power Producing Devices  

SciTech Connect

Herein is discussed the instrumentation and control requirements for achieving the goal of operating multiple Distributed Energy (DE) devices in parallel to regulate local voltage. The process for establishing the flexible laboratory control and data acquisition system that allows for the integration of multiple Distributed Energy (DE) devices in XXXX Laboratory's Distributed Energy - Communications and Controls Laboratory (DECC) is discussed. The DE devices control local distribution system voltage through dynamic reactive power production. Although original efforts were made to control the reactive power (RP) output using information from commercially available meters specifically designed for monitoring and analyzing electric power values, these "intelligent" meters did not provide the flexibility needed. A very flexible and capable real-time monitoring and control system was selected after the evaluation of various methods of data acquisition (DAQ) and control. The purpose of this paper is to describe the DAQ and controls system development. The chosen controller is a commercially available real-time controller from dSPACE. This controller has many excellent features including a very easy programming platform through Simulink and Matlab's Real Time Workshop. The dSPACE system proved to provide both the flexibility and expandability needed to integrate and control the RP producing devices under consideration. The desire was to develop controls with this flexible laboratory instrumentation and controls setup that could be eventually be included in an embedded controller on a DE device. Some experimental results are included that clearly show that some functional control strategies are currently being tested.

Foster, Jason [ORNL; Rizy, D Tom [ORNL; Kueck, John D [ORNL

2007-01-01T23:59:59.000Z

295

Design of control system for hydraulic lifting platform with jack-up wind-power installation vessel  

Science Conference Proceedings (OSTI)

Jack-up wind-power installation vessel is the most important tool in construction of wind farm. And the control system for hydraulic lifting platform is the key point of jack-up wind-power installation vessel. Therefore the design of the control system ... Keywords: hydraulic control, hydraulic lifting platform, programmable logic controller, wind-power

Xuejin Yang; Dingfang Chen; Mingwang Dong; Taotao Li

2012-11-01T23:59:59.000Z

296

Multivariable robust control of a power plant deaerator  

Science Conference Proceedings (OSTI)

The paper addresses the design of a robust controller for the deaerator of the Experimental Breeder Reactor-II (EBR-II) using the Linear Quadratic Gaussian with Loop Transfer Recovery (LQG/LTR) procedure. At present, classical PI controllers are used to control the deaerator. When the operating condition changes, the system is disturbed, or a fault occurs, the PI controllers may fail to maintain the desired performance which in turn deteriorates the performance of other components of the condensate system. This was a motivation to design a robust controller that can accommodate system faults and obtain a reasonable behavior for a wide range of model uncertainty. The designed controller has the following desirable features: (a) it provides the desired performance despite a considerable change in the operating condition, (b) it accommodates some of the failures that can occur, and (c) it provides the choice of penalizing one variable over another. The controller design is tested for robustness by varying the system operating condition and simulating a steam valve failure. The set of non-linear simulations using the Modular Modeling System (MMS) and the Advanced Continuous Simulation Language (ACSL) is included.

Ben-Abdennour, A.; Lee, K.Y.; Edwards, R.M. (Pennsylvania State Univ., University Park (United States))

1993-03-01T23:59:59.000Z

297

Control of power to an inductively heated part  

DOE Patents (OSTI)

A process for induction hardening a part to a desired depth with an AC signal applied to the part from a closely coupled induction coil includes measuring the voltage of the AC signal at the coil and the current passing through the coil; and controlling the depth of hardening of the part from the measured voltage and current. The control system determines parameters of the part that are functions of applied voltage and current to the induction coil, and uses a neural network to control the application of the AC signal based on the detected functions for each part.

Adkins, Douglas R. (1620 Adelita Dr. NE., Albuquerque, NM 87112); Frost, Charles A. (1039 Red Oaks Loop NE., Albuquerque, NM 87122); Kahle, Philip M. (528 Longwood Loop NE., Rio Rancho, NM 87124); Kelley, J. Bruce (13200 Blue Corn Maiden Trail NE., Albuquerque, NM 87112); Stanton, Suzanne L. (2805 Palo Alto NE., Albuquerque, NM 87112)

1997-01-01T23:59:59.000Z

298

Amp-hour counting control for PV hybrid power systems  

SciTech Connect

The performance of an amp-hour (Ah) counting battery charge control algorithm has been defined and tested using the Digital Solar Technologies MPR-9400 microprocessor based PV hybrid charge controller. This work included extensive field testing of the charge algorithm on flooded lead-antimony and valve regulated lead-acid (VRLA) batteries. The test results after one-year have demonstrated that PV charge utilization, battery charge control, and battery state of charge (SOC) has been significantly improved by providing maximum charge to the batteries while limiting battery overcharge to manufacturers specifications during variable solar resource and load periods.

Hund, T.D. [Sandia National Labs., Albuquerque, NM (United States); Thompson, B. [Biri Systems, Ithaca, NY (United States)

1997-06-01T23:59:59.000Z

299

Genetic-Algorithm-Based Adaptive Control of Superheat Steam Temperature on a Power Plant Boiler  

Science Conference Proceedings (OSTI)

Superheat steam temperature control is critical to the normal and optimal operation of a power plant. Usually, cascade Proportional Integral Derivative (PID) control system is introduced to regulate the superheat temperature with the PID parameters fixed ... Keywords: Genetic Algorithm, Adaptive Control, Recursive Least Squares, Robustness

Yonghong Huang; Xuejun Yang

2008-12-01T23:59:59.000Z

300

Intelligent predictive control of a power plant with evolutionary programming optimizer and neuro-fuzzy identifier  

Science Conference Proceedings (OSTI)

An intelligent predictive controller is implemented to control a fossil fuel power unit. This controller is a non-model based system that uses a self-organized neuro-fuzzy identifier to predict the response of the plant in a future time interval. The ...

H. Ghezelayagh; K. Y. Lee

2002-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Robust and low complexity rate control for solar powered sensors  

Science Conference Proceedings (OSTI)

This paper is concerned with solar driven sensors deployed in an outdoor environment. We present feedback controllers which adapt parameters of the application such that a maximal utility is obtained while respecting the time-varying amount of available ...

Clemens Moser; Lothar Thiele; Davide Brunelli; Luca Benini

2008-03-01T23:59:59.000Z

302

Integrated Computing, Communication, and Distributed Control of Deregulated Electric Power Systems  

SciTech Connect

Restructuring of the electricity market has affected all aspects of the power industry from generation to transmission, distribution, and consumption. Transmission circuits, in particular, are stressed often exceeding their stability limits because of the difficulty in building new transmission lines due to environmental concerns and financial risk. Deregulation has resulted in the need for tighter control strategies to maintain reliability even in the event of considerable structural changes, such as loss of a large generating unit or a transmission line, and changes in loading conditions due to the continuously varying power consumption. Our research efforts under the DOE EPSCoR Grant focused on Integrated Computing, Communication and Distributed Control of Deregulated Electric Power Systems. This research is applicable to operating and controlling modern electric energy systems. The controls developed by APERC provide for a more efficient, economical, reliable, and secure operation of these systems. Under this program, we developed distributed control algorithms suitable for large-scale geographically dispersed power systems and also economic tools to evaluate their effectiveness and impact on power markets. Progress was made in the development of distributed intelligent control agents for reliable and automated operation of integrated electric power systems. The methodologies employed combine information technology, control and communication, agent technology, and power systems engineering in the development of intelligent control agents for reliable and automated operation of integrated electric power systems. In the event of scheduled load changes or unforeseen disturbances, the power system is expected to minimize the effects and costs of disturbances and to maintain critical infrastructure operational.

Bajura, Richard; Feliachi, Ali

2008-09-24T23:59:59.000Z

303

Variable Renewable Generation can Provide Balancing Control to the Electric Power System (Fact Sheet)  

DOE Green Energy (OSTI)

As wind and solar plants become more common in the electric power system, they may be called on to provide grid support services to help maintain system reliability. For example, through the use of inertial response, primary frequency response, and automatic generation control (also called secondary frequency response), wind power can provide assistance in balancing the generation and load on the system. These active power (i.e., real power) control services have the potential to assist the electric power system in times of disturbances and during normal conditions while also potentially providing economic value to consumers and variable renewable generation owners. This one-page, two-sided fact sheet discusses the grid-friendly support and benefits renewables can provide to the electric power system.

Not Available

2013-09-01T23:59:59.000Z

304

CONCEPTUAL DESIGN AND OPTIMAL POWER CONTROL STRATEGY FOR AN ECO?FRIENDLY HYBRID VEHICLE  

Science Conference Proceedings (OSTI)

This paper presents a new concept for a hybrid vehicle using a torque and speed splitting technique. It is implemented by the newly developed controller in combination with a two degree of freedom epicyclic gear transmission. This approach enables optimization of the power split between the less powerful electrical motor and more powerful engine while driving a car load. The power split is fundamentally a dual?energy integration mechanism as it is implemented by using the epicyclic gear transmission that has two inputs and one output for a proper power distribution. The developed power split control system manages the operation of both the inputs to have a known output with the condition of maintaining optimum operating efficiency of the internal combustion engine and electrical motor. This system has a huge potential as it is possible to integrate all the features of hybrid vehicle known to?date such as the regenerative braking system

N. Mir Nasiri; Frederick T. A. Chieng

2011-01-01T23:59:59.000Z

305

Power Supply Changes for NSTX Resistive Wall Mode Coils  

SciTech Connect

The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. Prior to 2004, the NSTX power system was feeding twelve (12) circuits in the machine. In 2004 the Resistive Wall Mode (RWM) Coils were installed on the machine to correct error fields. There are six of these coils installed around the machine in the mid-plane. Since these coils need fast and accurate controls, a Switching Power Amplifier (SPA) with three sub-units was procured, installed and commissioned along with other power loop components. Two RWM Coils were connected in series and fed from one SPA sub-unit. After the initial RWM campaign, operational requirements evolved such that each of the RWM coils now requires separate power and control. Hence a second SPA with three sub-units has been procured and installed. The second unit is of improved design and has the controls and power components completely isolated. The existing thyristor rectifier is used as DC Link to both of the Switching Power Amplifiers. The controls for the RWM are integrated into the overall computer control of the DC Power systems for NSTX. This paper describes the design changes in the RWM Power system for NSTX.

Ramakrishnan, S S.

2013-06-28T23:59:59.000Z

306

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360.degree./n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1997-01-01T23:59:59.000Z

307

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360{degree}/n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load. 7 figs.

Shimer, D.W.; Lange, A.C.

1997-03-11T23:59:59.000Z

308

Identification of Critical Voltage Control Areas and Determination of Required Reactive Power Reserves  

Science Conference Proceedings (OSTI)

The objective of this research project is to investigate and devise a methodology for identifying areas in power systems that are prone to voltage instability under particular operating conditions and contingencies. These areas, which are prone to instability due to their lack of reactive power reserves, are referred to as critical voltage control areas (VCAs). Once VCAs are identified, methods of determining their adequate reactive power reserve requirements to ensure secure system operation under all c...

2008-12-09T23:59:59.000Z

309

HVDC Control Strategies to Improve Transient Stability in Interconnected Power Systems  

E-Print Network (OSTI)

This paper presents three HVDC modulation strategies to improve transient stability in an interconnected power system. AC variables such as rotor speeds, voltage phasors, and tieline power flows are used as input to the controller that modifies the power flow settings through the HVDC-links. The proposed techniques are tested on the IEEE 24-Bus reliability test system and critical clearing times obtained for several contingencies are analyzed. The paper shows that HVDC modulation can lead to substantial improvement in transient stability.

J. Hazra; Y. Phulpin; D. Ernst

2009-01-01T23:59:59.000Z

310

Control of a Powered Ankle–Foot Prosthesis Based on a Neuromuscular Model  

E-Print Network (OSTI)

Control schemes for powered ankle-foot prostheses rely upon fixed torque-ankle state relationships obtained from measurements of intact humans walking at target speeds and across known terrains. Although effective at their ...

Geyer, Hartmut

311

Cost of Providing Ancillary Services from Power Plants: Reactive Supply and Voltage Control  

Science Conference Proceedings (OSTI)

This report provides a methodology for determining the variable costs of generating and supplying reactive power to a transmission system, via the generator step-up transformer, for system voltage control. The report examines the costs of additional energy losses, maintenance, repair, and plant aging associated with the generation of reactive power. TR-107270-V3SI contains System of International units.

1997-09-02T23:59:59.000Z

312

MEC-IDC: joint load balancing and power control for distributed Internet Data Centers  

Science Conference Proceedings (OSTI)

Internet Data Center (IDC) supports the reliable operations of many important Internet on-line services. As the demand on Internet services and cloud computing keep increasing in recent years, the power usage associated with IDC operations has been uprising ... Keywords: cyber-physical system, distributed internet data center, load balancing, power control

Lei Rao; Xue Liu; Marija Ilic; Jie Liu

2010-04-01T23:59:59.000Z

313

Effect of radial power distribution on MITR-II fuel element and control blade worth  

Science Conference Proceedings (OSTI)

This summary has been prepared to document and discuss several effects on fuel element and control blade reactivity worths that occur due to changes in the radial power distribution of the 5-MW(t) Massachusetts Institute of Technology Research Reactor (MITR-II). These results were obtained from reactor physics measurements and core power distribution calculations made during the past decade.

Bernard, J.A.; Kwok, K.S.; Lanning, D.D.; Clark, L.L. Jr.

1985-01-01T23:59:59.000Z

314

Distributed Battery Control to Improve Peak Power Shaving Efficiency in Data Centers  

E-Print Network (OSTI)

Distributed Battery Control to Improve Peak Power Shaving Efficiency in Data Centers Baris Aksanli, Eddie Pettis and Tajana S. Rosing UCSD, Google Stored energy in batteries can be used to cap peak power.8% 99% 91.5% 84% Battery Configuration StudyBattery Configuration Study Goal: Improve the overall

Simunic, Tajana

315

Network reconfiguration of distributed controlled homogenous power inverter network using composite Lyapunov function based reachability bound  

Science Conference Proceedings (OSTI)

We outline a methodology to determine the reachability bound of a homogeneous interactive power network (IPN) with wireless distributed control by using a piecewise linear (PWL) model of the system. By formulating a convex optimization problem based ... Keywords: Lyapunov stability, Markov-chain model, linear matrix inequality, piecewise linear systems, reaching conditions, switching power converters

Sudip K. Mazumder; Kaustuva Acharya; Muhammad Tahir

2007-07-01T23:59:59.000Z

316

Extremum seeking control techniques applied to photovoltaic systems with multimodal power curves  

E-Print Network (OSTI)

) Current(A) 0 200 320025 I-V curve P-V curve VMPP Power(W) 1000 Fig. 1. Photovoltaic cell I-V and P generator method, open-circuit voltage photovoltaic cell test method, incremental conductance method (CI) [5Extremum seeking control techniques applied to photovoltaic systems with multimodal power curves

Recanati, Catherine

317

CHANCE CONSTRAINED OPTIMAL POWER FLOW: RISK-AWARE NETWORK CONTROL UNDER UNCERTAINTY  

E-Print Network (OSTI)

short-term demand changes locally) and are largely not of a data-driven, algorithmic and distributed. Additionally, only some real-time data is actually used by the grid to respond to evolving conditions. All Power Flow (OPF), routinely used by the electric power industry to re-dispatch hourly controllable

Bienstock, Daniel

318

Optimal control in energy conversion of small wind power systems with permanent-magnet-synchronous-generators  

Science Conference Proceedings (OSTI)

This paper presents the results of experimental investigation of a low-power wind energy conversion system (WECS), based on a permanent-magnet synchronous generator (PMSG) connected directly to the turbine. A development system was built in order to ... Keywords: hardware-in-the-loop simulation, maximum power point tracking, optimal control, permanent-magnet synchronous generator, wind system

C. Vlad; I. Munteanu; A. I. Bratcu; E. Ceanga

2008-07-01T23:59:59.000Z

319

Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems  

E-Print Network (OSTI)

Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems B. Beltran, T. Ahmed power generation in variable speed wind energy conversion systems (VS-WECS). These systems have two (National Renewable Energy Laboratory) wind turbine simulator FAST (Fatigue, Aerodynamics, Structures

Brest, Université de

320

Information Foraging in Nuclear Power Plant Control Rooms  

SciTech Connect

nformation foraging theory articulates the role of the human as an 'informavore' that seeks information and follows optimal foraging strategies (i.e., the 'information scent') to find meaningful information. This paper briefly reviews the findings from information foraging theory outside the nuclear domain and then discusses the types of information foraging strategies operators employ for normal and off-normal operations in the control room. For example, operators may employ a predatory 'wolf' strategy of hunting for information in the face of a plant upset. However, during routine operations, the operators may employ a trapping 'spider' strategy of waiting for relevant indicators to appear. This delineation corresponds to information pull and push strategies, respectively. No studies have been conducted to determine explicitly the characteristics of a control room interface that is optimized for both push and pull information foraging strategies, nor has there been empirical work to validate operator performance when transitioning between push and pull strategies. This paper explores examples of control room operators as wolves vs. spiders and con- cludes by proposing a set of research questions to investigate information foraging in control room settings.

R.L. Boring

2011-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

EPRI Power Electronics-Based Transmission Controllers Reference Book ("The Gold Book")  

Science Conference Proceedings (OSTI)

EPRI is sponsoring development of a first edition of the EPRI Power Electronics-Based Transmission Controllers Reference Book. The reference book will provide a broad overview on power electronics-based controllers0150with information on historical perspectives, basic design considerations, factory testing, site installations, commissioning, operating performance, operation and maintenance, and future trends. The book will assist users in planning, developing, installing, and utilizing this technology.

2006-12-05T23:59:59.000Z

322

Commerce study looks at cost of pollution control for fossil-fuel power industry  

SciTech Connect

Environmental controls for fossil-fuel power plants consumed 1.3 percent of the national fuel used in 1974, with the largest demand going for sulfur dioxide emission control. Projections for power plant consumption to meet environmental standards range as high as eight percent in the 1980s. Less-energy-consuming systems include coal blending, tall stacks, and supplementary control systems; while high consumers are using coal washing operations in place of scrubbers, fuel transportation, conversion to acceptable fuels, waste heat disposal, and particulate controls. A summary table presents sulfur dioxide regulations in terms of their goals and their anticipated minimum and maximum fuel consumption. (DCK)

1977-06-01T23:59:59.000Z

323

The ISR Argus 500 system - control of the beam transfer power supplies by the Argus 500 computer operators manual  

E-Print Network (OSTI)

The ISR Argus 500 system - control of the beam transfer power supplies by the Argus 500 computer operators manual

Kemp, D

1970-01-01T23:59:59.000Z

324

The study of multimode power control system for MW variable-speed wind turbine  

Science Conference Proceedings (OSTI)

Wind energy is a viable option to complement other types of pollution-free generation. In the past constant-speed wind turbine is used for the limitation of the control technology and manufacturing technology. But this kind wind turbine has low efficiency ... Keywords: feed-forward compensator, loop-shaping, multimode power control system, pitch controller, speed controller, the shaft system model, wind turbine

Dingguo Wu; Zhixin Wang

2008-10-01T23:59:59.000Z

325

Fossil Power Plant Outage Scoping and Scope Control  

Science Conference Proceedings (OSTI)

This document provides detailed guidance for outage scope planning and control. It covers such topics as long-range business asset management tracking and inclusion into outage scope and contingency planning. It provides guidance on developing the outage plan, including typical criteria for the baseline budget, developing and using a monitoring plan and metrics, and developing an assessment plan for outage scope development and execution. The scope identification and approval processes are discussed as w...

2007-12-19T23:59:59.000Z

326

Control Strategies for Distributed Energy Resources to Maximize the Use of Wind Power in Rural Microgrids  

Science Conference Proceedings (OSTI)

The focus of this paper is to design control strategies for distributed energy resources (DERs) to maximize the use of wind power in a rural microgrid. In such a system, it may be economical to harness wind power to reduce the consumption of fossil fuels for electricity production. In this work, we develop control strategies for DERs, including diesel generators, energy storage and demand response, to achieve high penetration of wind energy in a rural microgrid. Combinations of centralized (direct control) and decentralized (autonomous response) control strategies are investigated. Detailed dynamic models for a rural microgrid are built to conduct simulations. The system response to large disturbances and frequency regulation are tested. It is shown that optimal control coordination of DERs can be achieved to maintain system frequency while maximizing wind power usage and reducing the wear and tear on fossil fueled generators.

Lu, Shuai; Elizondo, Marcelo A.; Samaan, Nader A.; Kalsi, Karanjit; Mayhorn, Ebony T.; Diao, Ruisheng; Jin, Chunlian; Zhang, Yu

2011-10-10T23:59:59.000Z

327

OVERVIEW OF A RECONFIGURABLE SIMULATOR FOR MAIN CONTROL ROOM UPGRADES IN NUCLEAR POWER PLANTS  

SciTech Connect

This paper provides background on a reconfigurable control room simulator for nuclear power plants. The main control rooms in current nuclear power plants feature analog technology that is growing obsolete. The need to upgrade control rooms serves the practical need of maintainability as well as the opportunity to implement newer digital technologies with added functionality. There currently exists no dedicated research simulator for use in human factors design and evaluation activities for nuclear power plant modernization in the U.S. The new research simulator discussed in this paper provides a test bed in which operator performance on new control room concepts can be benchmarked against existing control rooms and in which new technologies can be validated for safety and usability prior to deployment.

Ronald L. Boring

2012-10-01T23:59:59.000Z

328

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network (OSTI)

pressure controller of a steam turbine. For the purpose ofthe response of steam turbines to governing action: R = 0.05cycle plants. The steam turbines of these plants are most

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

329

The Power Decoupling Control for Wind Power Converter Based on a Novel Speed Sensor-Less  

Science Conference Proceedings (OSTI)

Doubly fed induction generators based wind turbines are today one of the most widely used generation systems in wind farms. The stator is directly connected to the constant frequency three phase grid and the rotor currents are appropriately controlled ...

Zhang Jia-ming; Fu Yang

2009-10-01T23:59:59.000Z

330

Designing power system simulators for the smart grid: combining controls, communications, and electro-mechanical dynamics  

Science Conference Proceedings (OSTI)

Open source software has a leading role in research on simulation technology for electrical power systems. Research simulators demonstrate new features for which there is nascent but growing demand not yet provided for by commercial simulators. Of particular interest is the inclusion of models of software-intensive and communication-intensive controls in simulations of power system transients. This paper describes two features of the ORNL power system simulator that help it meet this need. First is its use of discrete event simulation for all aspects of the model: control, communication, and electro-mechanical dynamics. Second is an interoperability interface that enables the ORNL power system simulator to be integrated with existing, discrete event simulators of digital communication systems. The paper concludes with a brief discussion of how these aspects of the ORNL power system simulator might be inserted into production-grade simulation tools.

Nutaro, James J [ORNL

2011-01-01T23:59:59.000Z

331

Improved Power Control in the Palm of Your Hand | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Improved Power Control in the Palm of Your Hand Improved Power Control in the Palm of Your Hand Improved Power Control in the Palm of Your Hand November 7, 2011 - 2:11pm Addthis Silicon carbide thyristors, developed through a partnership between the Energy Department's Sandia National Lab and GeneSiC Semiconductor, are key to utility-scale power conversion. Learn more about this technology, which won a 2011 R&D 100 award. Dr. Imre Gyuk Dr. Imre Gyuk Energy Storage Program Manager, Office of Electricity Delivery and Energy Reliability How does it work? The GeneSic thyristor -- an electronic switch -- is based on on silicon carbide (SiC), which can operate at much higher temperatures than silicon. This allows the device to handle 10 times the voltage, and switch 100 times faster, than its silicon-based competition.

332

Diversity Strategies for Nuclear Power Plant Instrumentation and Control Systems  

Science Conference Proceedings (OSTI)

This report presents the technical basis for establishing acceptable mitigating strategies that resolve diversity and defense-in-depth (D3) assessment findings and conform to U.S. Nuclear Regulatory Commission (NRC) requirements. The research approach employed to establish appropriate diversity strategies involves investigation of available documentation on D3 methods and experience from nuclear power and nonnuclear industries, capture of expert knowledge and lessons learned, determination of best practices, and assessment of the nature of common-cause failures (CCFs) and compensating diversity attributes. The research described in this report does not provide guidance on how to determine the need for diversity in a safety system to mitigate the consequences of potential CCFs. Rather, the scope of this report provides guidance to the staff and nuclear industry after a licensee or applicant has performed a D3 assessment per NUREG/CR-6303 and determined that diversity in a safety system is needed for mitigating the consequences of potential CCFs identified in the evaluation of the safety system design features. Succinctly, the purpose of the research described in this report was to answer the question, 'If diversity is required in a safety system to mitigate the consequences of potential CCFs, how much diversity is enough?' The principal results of this research effort have identified and developed diversity strategies, which consist of combinations of diversity attributes and their associated criteria. Technology, which corresponds to design diversity, is chosen as the principal system characteristic by which diversity criteria are grouped to form strategies. The rationale for this classification framework involves consideration of the profound impact that technology-focused design diversity provides. Consequently, the diversity usage classification scheme involves three families of strategies: (1) different technologies, (2) different approaches within the same technology, and (3) different architectures within the same technology. Using this convention, the first diversity usage family, designated Strategy A, is characterized by fundamentally diverse technologies. Strategy A at the system or platform level is illustrated by the example of analog and digital implementations. The second diversity usage family, designated Strategy B, is achieved through the use of distinctly different technologies. Strategy B can be described in terms of different digital technologies, such as the distinct approaches represented by general-purpose microprocessors and field-programmable gate arrays. The third diversity usage family, designated Strategy C, involves the use of variations within a technology. An example of Strategy C involves different digital architectures within the same technology, such as that provided by different microprocessors (e.g., Pentium and Power PC). The grouping of diversity criteria combinations according to Strategies A, B, and C establishes baseline diversity usage and facilitates a systematic organization of strategic approaches for coping with CCF vulnerabilities. Effectively, these baseline sets of diversity criteria constitute appropriate CCF mitigating strategies for digital safety systems. The strategies represent guidance on acceptable diversity usage and can be applied directly to ensure that CCF vulnerabilities identified through a D3 assessment have been adequately resolved. Additionally, a framework has been generated for capturing practices regarding diversity usage and a tool has been developed for the systematic assessment of the comparative effect of proposed diversity strategies (see Appendix A).

Wood, Richard Thomas [ORNL; Belles, Randy [ORNL; Cetiner, Mustafa Sacit [ORNL; Holcomb, David Eugene [ORNL; Korsah, Kofi [ORNL; Loebl, Andy [ORNL; Mays, Gary T [ORNL; Muhlheim, Michael David [ORNL; Mullens, James Allen [ORNL; Poore III, Willis P [ORNL; Qualls, A L [ORNL; Wilson, Thomas L [ORNL; Waterman, Michael E. [U.S. Nuclear Regulatory Commission

2010-02-01T23:59:59.000Z

333

Solar powered automatic turn-on control (spa-toc) unit and method  

SciTech Connect

Orderly control of power applied by a photovoltaic solar panel d.c. source to a load is attained despite varying long and short term solar conditions by coupling power from the panel to an inverter in response to the panel voltage exceeding a predetermined level and preventing coupling of power from the panel to the inverter in response to the panel voltage being less than a predetermined level. The switching frequency of the inverter is controlled in response to the panel voltage so that approximately maximum power which the panel is capable of generating is supplied to the inverter for the incident solar energy on the panel at a given temperature. Power is supplied to the inverter by a series switch between the panel and inverter. The switch is activated into a conducting state in response to the panel voltage exceeding a predetermined value. The panel voltage controls the turn-on and turn-off levels of the series switch by a hysteresis effect, provided by connecting a dummy power dissipating load in shunt with the panel while the series switch is cut off. The dummy load has a value causing the panel output voltage to be less than the voltage for maximum panel output power. A similar series switch and hysteresis control is provided for control circuitry for the inverter. The series switch for supplying power to the control circuitry can be activated in response to the same voltage which activates the series switch for the inverter, or in response to a different voltage level.

Baker, R.H.

1982-06-01T23:59:59.000Z

334

Advanced control for power density maximization of the brushless DC generator  

E-Print Network (OSTI)

This dissertation proposes a novel control technique for power density maximization of the brushless DC (BLDC) generator which is a nonsinusoidal power supply system. In a generator of given rating, the weight and size of the system affect the fuel consumption directly, therefore power density is one of the most important issues in a stand-alone generator. Conventional rectification methods cannot achieve the maximum power possible because of a distorted or unsuitable current waveform. The optimal current waveform for maximizing power density and minimizing machine size and weight in a nonsinusoidal power supply system has been proposed theoretically and verified by simulation and experimental work. Also, various attributes of practical interest are analyzed and simulated to investigate the impact on real systems.

Lee, Hyung-Woo

2003-12-01T23:59:59.000Z

335

Drum type fossil fueled power plant control based on fuzzy inverse MIMO model  

Science Conference Proceedings (OSTI)

In this paper, a new fuzzy controller is proposed based on inverse model of boiler-turbine system. Gain scheduling scheme is used to keep feedback rule as close as possible to optimal condition while generating plant Input/Output data. Interaction between ... Keywords: ANFIS, drum type fossil fueled power plant (FFPP), interaction, inverse model control, nonlinear model, robustness

Ali Ghaffari; Mansour Nikkhah Bahrami; Hesam Parsa

2006-06-01T23:59:59.000Z

336

SNAP I POWER CONVERSION SYSTEM CONTROL DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959  

SciTech Connect

Development of the control elements for the SNAP 1 power conversion system is described. A description of test and prototype hardware and performance data are included. The control package in its final design is a combination of regulator and speed-sensitive feedback which provides satisfactory steady-state operation and serves as a mechanism correction for system disturbances. (J.R.D.)

Dauterman, W.E.; Mueller, M.W.; Viton, E.J.

1960-06-20T23:59:59.000Z

337

Weight optimisation for iterative distributed model predictive control applied to power networks  

Science Conference Proceedings (OSTI)

This paper presents a weight tuning technique for iterative distributed Model Predictive Control (MPC). Particle Swarm Optimisation (PSO) is used to optimise both the weights associated with disturbance rejection and those associated with achieving consensus ... Keywords: Distributed model predictive control, Multi-agent, Particle swarm optimisation, Power networks, Smart grids, Weight tuning

Paul Mc Namara; Rudy R. Negenborn; Bart De Schutter; Gordon Lightbody

2013-01-01T23:59:59.000Z

338

Control system and method for a power delivery system having a continuously variable ratio transmission  

DOE Patents (OSTI)

A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for minimum fuel consumption. CVT ratio is controlled as a function of commanded power or torque and measured load, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristic for any load placed on the engine. 4 figs.

Frank, A.A.

1984-07-10T23:59:59.000Z

339

Control system and method for a power delivery system having a continuously variable ratio transmission  

DOE Patents (OSTI)

A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for minimum fuel consumption. CVT ratio is controlled as a function of commanded power or torque and measured load, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristic for any load placed on the engine.

Frank, Andrew A. (1034 Hillside Ave., Madison, WI 53705)

1984-01-01T23:59:59.000Z

340

Evolution of the CERN Power Converter Function Generator/Controller for Operation in Fast Cycling Accelerators  

E-Print Network (OSTI)

Power converters in the LHC are controlled by the second generation of an embedded computer known as a Function Generator/Controller (FGC2). Following the success of this control system, new power converter installations at CERN will be based around an evolution of the design – a third generation called FGC3. The FGC3 will initially be used in the PS Booster and Linac4. This paper compares the hardware of the two generations of FGC and details the decisions made during the design of the FGC3.

Calcoen, D; Semanaz, PF

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Flux stability and power control in the Soviet RBMK-1000 reactors  

SciTech Connect

As a result of the Chernobyl accident, the Soviets have studied and implemented various design changes to improve the safety of the RBMK reactors. The safety measurements include modifications of the control rod configuration, fuel enrichment increase from 2.0 to 2.4 weight percent U-235, and installation of additional supplemental absorbers. The purpose of this study is to investigate the effects of increased fuel enrichment, different control rod positions, and supplemental absorber loadings on reactivity control, power distribution within the large RBMK core, and relative stability against power oscillations.

Meriwether, G.H.; McNeece, J.P.

1993-08-01T23:59:59.000Z

342

Agent based control of power systems, ForskEL (Smart Grid Project) | Open  

Open Energy Info (EERE)

Agent based control of power systems, ForskEL (Smart Grid Project) Agent based control of power systems, ForskEL (Smart Grid Project) Jump to: navigation, search Project Name Agent based control of power systems, ForskEL Country Denmark Coordinates 56.26392°, 9.501785° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":56.26392,"lon":9.501785,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

343

220 kV SSSC device for power flow control (Smart Grid Project) | Open  

Open Energy Info (EERE)

kV SSSC device for power flow control (Smart Grid Project) kV SSSC device for power flow control (Smart Grid Project) Jump to: navigation, search Project Name 220 kV SSSC device for power flow control Country Spain Headquarters Location Catalonia, Spain Coordinates 41.59116°, 1.520862° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.59116,"lon":1.520862,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

344

Optimal control system design for IGCC power plants with CO2 capture  

Science Conference Proceedings (OSTI)

Designing an optimal control system for an integrated gasification combined cycle (IGCC) power plant with CO2 capture addresses the challenge of efficiently operating and controlling a coal-fed IGCC plant with the desired extent of CO2 capture in the face of disturbances without violating operational and environmental constraints. The control system design needs to optimize a desired scalar objective function while satisfying all the operational and environmental constraints in the presence of measured and unmeasured disturbances. Various objective functions can be considered for the control system design such as maximization of profit, maximization of the power produced, or minimization of the auxiliary power. The design of such a control system makes the plant suitable to play an active role in the smart grid era as the plant will have the required agility. In addition, other penalty function(s) such as emission penalties for CO2 or other criteria pollutants can be considered in the framework as well as losses associated with any hydrogen or carbon monoxide loses. The proposed control system design is performed in two stages. In the first stage, a top-down analysis is performed to generate a list of controlled, manipulated, and disturbance variables considering a scalar operational objective and other process constraints. In the second stage, a bottom-up approach for simultaneous design of the control structure and the controllers is used. In this paper, the first stage of the two-stage approach is applied to the IGCC’s acid gas removal (AGR) process which removes both H2S and CO2 from the shifted synthesis gas. While these results are still preliminary, they demonstrate the application of the proposed approach for a commercial-scale plant and show some interesting results related to controlled variable selection. Such an approach can be followed not only to design control systems for new power plants, but also to retrofit control systems for existing plants with suitable modifications.

Jones, D.; Bhattacharyya, D.; Turton, R.; Zitney, S.

2012-01-01T23:59:59.000Z

345

Grid-connected and control of MPPT for wind power generation systems based on the SCIG  

Science Conference Proceedings (OSTI)

This paper adopts a main circuit structure with back-to-back PWM converter, in which generator-side using direct torque control method, and grid-side adopts three-phase VSR inner current decoupling control based feed forward control algorithms, and this ... Keywords: back-to-back, grid-connected, maximum power point tracking (MPPT), squirrel cage induction generator (SCIG), wind-turbine generation system

Yidong Chen; Yulin Yang; Liqiao Wang; Zhiyun Jia; Weiyang Wu

2010-03-01T23:59:59.000Z

346

Optimum system design of a three-phase rectifier-inverter type of frequency changer  

SciTech Connect

Steadily decreasing prices and improved performance of semiconductor devices have raised expectations towards the development and large-scale application of motor-mounted static converters. In view of this, the design of a rectifier-inverter type of frequency changer which requires very small reactive components is considered. Accordingly, rectifier and inverter PWM schemes which generate the minimum possible harmonic distortion are first discussed. By using a suitable analysis method, ''optimum'' design data are obtained for every major system component. Resulting reactive component values are shown to be considerably smaller than the ones required by typical rectifier-inverter structures. Predicted key results are verified by computer simulation.

Ziogas, P.D.; Kang, Y-G.; Stefanovic, V.R.

1985-09-01T23:59:59.000Z

347

Small scale ethanol production demonstration: comparison of packed versus plate rectifying column  

DOE Green Energy (OSTI)

The Johnson Environmental and Energy Center with assistance from the Madison County Farm Bureau Association received a grant in 1980 from the US Department of Energy to design, fabricate, and evaluate a small scale continuous ethanol plant. In 1981, the Center received a second DOE grant to compare the economics of replacing the plate rectifying column in the initial unit with a packed rectifying column. The results of the study indicate that the distillation unit with the packed rectifying column is capable of producing 14 gallons per hour of 170 proof ethanol. The energy ratio for distillation was a positive 2:1. Cost of the packed column was considerably less than the plate column. 1 reference, 19 figures, 9 tables.

Adcock, II, L E; Eley, M H; Schroer, B J

1982-07-01T23:59:59.000Z

348

Real-Time Power Control of Data Centers for Providing Regulation Service  

NLE Websites -- All DOE Office Websites (Extended Search)

Real-Time Power Control of Data Centers for Providing Regulation Service Real-Time Power Control of Data Centers for Providing Regulation Service Speaker(s): Ayse K. Coskun Date: November 19, 2013 - 12:00pm - 1:00pm Location: 90-3122 Seminar Host/Point of Contact: Girish Ghatikar Today's US power markets offer new opportunities for the energy consumers to reduce their energy costs by first promising an average consumption rate for the next hour and then by following a regulation signal broadcast by the independent system operators (ISOs), who need to match supply and demand in real time in presence of volatile and intermittent renewable energy generation. This talk proposes a management framework for the data centers to participate in the power markets. First, I will discuss how to solve the data center "regulation service (RS)" optimization problem to

349

Program on Technology Innovation: Network Management Technology Applied to Power Plant Instrumentation, Control, and Maintenance  

Science Conference Proceedings (OSTI)

Generic solutions developed for the information technology and telecommunications (IT-Telco) fields can benefit power plants willing to modernize instrumentation and control (I&C) equipment and maintenance tasks to take advantage of the expanded functionality of new technologies. This report investigates the applicability of generic network management products to help streamline power plant I&C and maintenance practices. Because of the competitive pressures of a large and expanding marketplace, such gene...

2005-07-25T23:59:59.000Z

350

Control scheme for power modulation of a free piston Stirling engine  

DOE Patents (OSTI)

The present invention relates to a control scheme for power modulation of a free-piston Stirling engine-linear alternator power generator system. The present invention includes connecting an autotransformer in series with a tuning capacitance between a linear alternator and a utility grid to maintain a constant displacement to piston stroke ratio and their relative phase angle over a wide range of operating conditions.

Dhar, Manmohan (Schenectady, NY)

1989-01-01T23:59:59.000Z

351

Self-powered automatic secondary air controllers for woodstoves and small furnaces  

DOE Patents (OSTI)

A controller for automatically regulating the supply of secondary combustion air to woodstoves and small furnaces. The controller includes a movable air valve for controlling the amount of secondary air admitted into the chamber. A self powered means monitors the concentration of combustible gases and vapors and actuates the movable air valve to increase the supply of secondary air in response to increasing concentrations of the combustible gases and vapors. The self-powered means can be two fluid filled sensor bulbs, one of which has a coating of a combustion catalyst. Alternatively, the self powered means can be two metallic stripes laminated together, one of which is coated with a combustion catalyst, and when heated, causes the air valve to actuate.

Siemer, Darryl D. (Idaho Falls, ID)

1991-01-01T23:59:59.000Z

352

A Repeated Game Formulation of Energy-Efficient Decentralized Power Control  

E-Print Network (OSTI)

Decentralized multiple access channels where each transmitter wants to selfishly maximize his transmission energy-efficiency are considered. Transmitters are assumed to choose freely their power control policy and interact (through multiuser interference) several times. It is shown that the corresponding conflict of interest can have a predictable outcome, namely a finitely or discounted repeated game equilibrium. Remarkably, it is shown that this equilibrium is Pareto-efficient under reasonable sufficient conditions and the corresponding decentralized power control policies can be implemented under realistic information assumptions: only individual channel state information and a public signal are required to implement the equilibrium strategies. Explicit equilibrium conditions are derived in terms of minimum number of game stages or maximum discount factor. Both analytical and simulation results are provided to compare the performance of the proposed power control policies with those already existing and exploiting the same information assumptions namely, those derived for the one-shot and Stackelberg games.

Mael Le Treust; Samson Lasaulce

2010-07-28T23:59:59.000Z

353

Distributed Hierarchical Control of Multi-Area Power Systems with Improved Primary Frequency Regulation  

SciTech Connect

The conventional distributed hierarchical control architecture for multi-area power systems is revisited. In this paper, a new distributed hierarchical control architecture is proposed. In the proposed architecture, pilot generators are selected in each area to be equipped with decentralized robust control as a supplementary to the conventional droop speed control. With the improved primary frequency control, the system frequency can be restored to the nominal value without the help of secondary frequency control, which reduces the burden of the automatic generation control for frequency restoration. Moreover, the low frequency inter-area electromechanical oscillations can also be effectively damped. The effectiveness of the proposed distributed hierarchical control architecture is validated through detailed simulations.

Lian, Jianming; Marinovici, Laurentiu D.; Kalsi, Karanjit; Du, Pengwei; Elizondo, Marcelo A.

2012-12-12T23:59:59.000Z

354

60% efficient 10-GHz power amplifier with dynamic drain bias control  

E-Print Network (OSTI)

Abstract—This paper describes the design, implementation, and characterization of a high-efficiency 10-GHz amplifier with dynamic drain bias control that maintains high efficiency over a range of output power levels. The power amplifier (PA) operates in class-E switched mode with 67 % drain efficiency at an output power of 20.3 dBm, 0.7 dB less than the specified maximum power for the device. A coupler and detector at the output of the PA provide a feedback signal to the drain-bias controller based on a 96 % efficient Buck dc–dc converter. When compared with a PA with constant drain bias (4 V), the average efficiency of the PA with dynamic biasing is improved by a factor of 1.4. Over an output power between 15–20 dBm, the drain bias varies from 2 to 4 V, and the efficiency improves from 22 % to 65 % at the lower power level. The efficiency includes the losses in the dc–dc converter. Index Terms—dc–dc converter, dynamic biasing, high efficiency, power amplifiers (PAs). I.

Narisi Wang; Vahid Yousefzadeh; Dragan Maksimovi?; Srdjan Paji?; Student Member; Student Member; Student Member; Zoya B. Popovi?

2004-01-01T23:59:59.000Z

355

Adaptive feedforward and feedback control schemes for sliding mode controlled power converters  

E-Print Network (OSTI)

Abstract—A major disadvantage of applying sliding mode control to dc/dc converters is that the steady-state switching frequency is affected by line and load variations. This is undesirable as it complicates the design of the input and output filters. To reduce switching frequency deviation in the events of line and load variations, an adaptive feedforward control scheme that varies the hysteresis band according to the change of line input voltage and an adaptive feedback control scheme that varies the control parameter (i.e., sliding coefficient) according to the change of the output load are proposed. This paper presents a thorough investigation into the problem and the effectiveness of the proposed solutions. In addition, methods of implementing the proposed adaptive control strategies are discussed. Experimental results confirm that the adaptive control schemes are capable of reducing the switching frequency variations caused by both line and load variations. Index Terms—Adaptive feedback control, adaptive feedforward control, buck converter, hysteresis modulation, pulse-width-modulation (PWM), sliding mode (SM)control. I.

Siew-chong Tan; Y. M. Lai; Chi K. Tse; Martin K. H. Cheung; Student Member

2006-01-01T23:59:59.000Z

356

Sorbent Activation Process for Mercury Control: Field Testing at the Ameren Meredosia Power Plant  

Science Conference Proceedings (OSTI)

The Electric Power Research Institute (EPRI) and the Illinois State Geological Survey have developed and patented a technology for the on-site production of activated carbon (AC). The basic approach of the sorbent activation process (SAP) is to use coal from the plant site to form AC for direct injection into flue gas upstream of the particulate control device for mercury adsorption. The SAP process is designed to help significantly reduce the cost of AC for power plant mercury control. This report summa...

2009-12-03T23:59:59.000Z

357

Dynamics and control modeling of the closed-cycle gas turbine (GT-HTGR) power plant  

SciTech Connect

The simulation if presented for the 800-MW(e) two-loop GT-HTGR plant design with the REALY2 transient analysis computer code, and the modeling of control strategies called for by the inherently unique operational requirements of a multiple loop GT-HTGR is described. Plant control of the GT-HTGR is constrained by the nature of its power conversion loops (PCLs) in which the core cooling flow and the turbine flow are directly related and thus changes in flow affect core cooling as well as turbine power. Additionally, the high thermal inertia of the reactor core precludes rapid changes in the temperature of the turbine inlet flow.

Bardia, A.

1980-02-01T23:59:59.000Z

358

Design of a Control Strategy for a Fuel Cell/Battery Hybrid Power Supply  

E-Print Network (OSTI)

The purpose of this thesis is to design hardware and a control strategy for a fuel cell/battery hybrid power supply. Modern fuel cell/battery hybrid power supplies can have 2 DC/DC converters: one converter for the battery and one for the fuel cell. The hardware for the power supply proposed in this thesis consists of a single DC/DC buck converter at the output terminals of the fuel cell. The battery does not have a DC/DC converter, and it is therefore passive in the system. The use of one single converter is attractive, because it reduces the cost of this power supply. This thesis proposes a method of controlling the fuel cell's DC/DC buck converter to act as a current source instead of a voltage source. This thesis will explain why using the fuel cell's buck converter to act as a current source is most appropriate. The proposed design techniques for the buck converter are also based on stiff systems theory. Combining a fuel cell and a battery in one power supply allows exploitation of the advantages of both devices and undermines their disadvantages. The fuel cell has a slow dynamic response time, and the battery has a fast dynamic response time to fluctuations in a load. A fuel cell has high energy density, and a battery has high power density. And the performance of the hybrid power supply exploits these advantages of the fuel cell and the battery. The controller designed in this thesis allows the fuel cell to operate in its most efficient region: even under dynamic load conditions. The passive battery inherits all load dynamic behavior, and it is therefore used for peaking power delivery, while the fuel cell delivers base or average power. Simulations will be provided using MATLAB/Simulink based models. And the results conclude that one can successfully control a hybrid fuel cell/battery power supply that decouples fluctuations in a load from the fuel cell with extremely limited hardware. The results also show that one can successfully control the fuel cell to operate in its most efficient region.

Smith, Richard C.

2009-08-01T23:59:59.000Z

359

Nonlinear power flow control applications to conventional generator swing equations subject to variable generation.  

Science Conference Proceedings (OSTI)

In this paper, the swing equations for renewable generators are formulated as a natural Hamiltonian system with externally applied non-conservative forces. A two-step process referred to as Hamiltonian Surface Shaping and Power Flow Control (HSSPFC) is used to analyze and design feedback controllers for the renewable generator system. This formulation extends previous results on the analytical verification of the Potential Energy Boundary Surface (PEBS) method to nonlinear control analysis and design and justifies the decomposition of the system into conservative and non-conservative systems to enable a two-step, serial analysis and design procedure. In particular, this approach extends the work done by developing a formulation which applies to a larger set of Hamiltonian Systems that has Nearly Hamiltonian Systems as a subset. The results of this research include the determination of the required performance of a proposed Flexible AC Transmission System (FACTS)/storage device to enable the maximum power output of a wind turbine while meeting the power system constraints on frequency and phase. The FACTS/storage device is required to operate as both a generator and load (energy storage) on the power system in this design. The Second Law of Thermodynamics is applied to the power flow equations to determine the stability boundaries (limit cycles) of the renewable generator system and enable design of feedback controllers that meet stability requirements while maximizing the power generation and flow to the load. Necessary and sufficient conditions for stability of renewable generators systems are determined based on the concepts of Hamiltonian systems, power flow, exergy (the maximum work that can be extracted from an energy flow) rate, and entropy rate.

Robinett, Rush D., III; Wilson, David Gerald

2010-05-01T23:59:59.000Z

360

Electric resonance-rectifier circuit for renewable energy conversion  

Science Conference Proceedings (OSTI)

Variable speed generators are used more frequently for converting the energy from renewable energy sources to electric energy. The power production form a variable speed generator is dependent on the electrical damping of the generator. In this paper

C. Boström; B. Ekergĺrd; M. Leijon

2012-01-01T23:59:59.000Z

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361

End-use load control for power system dynamic stability enhancement  

SciTech Connect

Faced with the prospect of increasing utilization of the transmission and distribution infrastructure without significant upgrade, the domestic electric power utility industry is investing heavily in technologies to improve network dynamic performance through a program loosely referred to as Flexible AC Transmission System (FACTS). Devices exploiting recent advances in power electronics are being installed in the power system to offset the need to construct new transmission lines. These devices collectively represent investment potential of several billion dollars over the next decade. A similar development, designed to curtail the peak loads and thus defer new transmission, distribution, and generation investment, falls under a category of technologies referred to as demand side management (DSM). A subset of broader conservation measures, DSM acts directly on the load to reduce peak consumption. DSM techniques include direct load control, in which a utility has the ability to curtail specific loads as conditions warrant. A novel approach has been conceived by Pacific Northwest National Laboratory (PNNL) to combine the objectives of FACTS and the technologies inherent in DSM to provide a distributed power system dynamic controller. This technology has the potential to dramatically offset major investments in FACTS devices by using direct load control to achieve dynamic stability objectives. The potential value of distributed versus centralized grid modulation has been examined by simulating the western power grid under extreme loading conditions. In these simulations, a scenario is analyzed in which active grid stabilization enables power imports into the southern California region to be increased several hundred megawatts beyond present limitations. Modeling results show distributed load control is up to 30 percent more effective than traditional centralized control schemes in achieving grid stability.

Dagle, J.E.; Winiarski, D.W.; Donnelly, M.K.

1997-02-01T23:59:59.000Z

362

FIRST SODIUM REACTOR EXPERIMENT (SRE) TEST OF HALLAM NUCLEAR POWER FACILITY (HNPF) CONTROL MATERIALS  

SciTech Connect

An experiment was conducted in the SRE to measure temperatures and neutron flux levels in and near a boron-containing simulated control rod. The data are being used to check analytical methods developed for prediction of control rod heat generation rates and maximum temperatures in this type of control rod in the Hallam Nuclear Power Facility. The maximum observed temperatures with a reactor power level of 20 Mw were 1363 deg F for a boron-- nickel alloy ring having a 0.105-in. radial clearance with the thimble and 1100 deg F for a boron -nickel alloy ring having a 0.020-in. radial clearance. The maximum temperature difference between the coolant and the control rod was 473 deg F. It is concluded that the expected greater heat generation rates in the Hallam reactor would prohibit the use of boron-containing absorber materials in a combined a him-safety rod. (auth)

Arneson, S.O.

1959-06-01T23:59:59.000Z

363

Dynamic Analysis and Stability of the Load Frequency Control in Two Area Power System with Steam Turbine  

Science Conference Proceedings (OSTI)

The aim of this paper is to model, analysis and simulation of load frequency control in two area power system and parameters variation effects. State equations of a LFC in two area power system for a steam turbine are proposed. Then by examining some ... Keywords: load frequency control, dynamic analysis, integral controller

Ghazanfar Shahgholian; Serareh Yazdekhasti; Pegah Shafaghi

2009-12-01T23:59:59.000Z

364

Particulate Control Device (PCD) Testing at the Power Systems Development Facility, Wilsonville, Alabama  

Science Conference Proceedings (OSTI)

One of the U.S. Department of Energy`s (DOE`s) objectives overseen by the Morgantown Energy Technology Center (METC) is to test systems and components for advanced coal-based power generation systems, including integrated gasification combined cycle (IGCC), pressurized fluidized-bed combustion (PFBC), and integrated gasification/fuel cell (IGFC) systems. Stringent particulate requirements for fuel gas for both combustion turbines and fuel cells that are integral to these systems. Particulates erode and chemically attack the blade surfaces in turbines, and cause blinding of the electrodes in fuel cells. Filtration of the hot, high-pressure, gasified coal is required to protect these units. Filtration can be accomplished by first cooling the gas, but the system efficiency is reduced. High-temperature, high-pressure, particulate control devices (PCDs) need to be developed to achieve high efficiency and to extend the lifetime of downstream components to acceptable levels. Demonstration of practical high-temperature PCDs is crucial to the evolution of advanced, high-efficiency, coal-based power generation systems. The intent at the Power Systems Development Facility (PSDF) is to establish a flexible test facility that can be used to (1) develop advanced power system components, such as high-temperature, high-pressure PCDs; (2) evaluate advanced power system configurations and (3) assess the integration and control issues of these advanced power systems.

Longanbach, J.R.

1995-12-01T23:59:59.000Z

365

Distributed control of reactive power flow in a radial distribution circuit with high photovoltaic penetration  

E-Print Network (OSTI)

We show how distributed control of reactive power can serve to regulate voltage and minimize resistive losses in a distribution circuit that includes a significant level of photovoltaic (PV) generation. To demonstrate the technique, we consider a radial distribution circuit with a single branch consisting of sequentially-arranged residential-scale loads that consume both real and reactive power. In parallel, some loads also have PV generation capability. We postulate that the inverters associated with each PV system are also capable of limited reactive power generation or consumption, and we seek to find the optimal dispatch of each inverter's reactive power to both maintain the voltage within an acceptable range and minimize the resistive losses over the entire circuit. We assume the complex impedance of the distribution circuit links and the instantaneous load and PV generation at each load are known. We compare the results of the optimal dispatch with a suboptimal local scheme that does not require any com...

Turitsyn, Konstantin; Backhaus, Scott; Chertkov, Michael

2009-01-01T23:59:59.000Z

366

Semantic security analysis of SCADA networks to detect malicious control commands in power grids  

Science Conference Proceedings (OSTI)

In the current generation of SCADA (Supervisory Control And Data Acquisition) systems used in power grids, a sophisticated attacker can exploit system vulnerabilities and use a legitimate maliciously crafted command to cause a wide range of system changes ... Keywords: contingency analysis, intrusion detection system, scada, semantic analysis

Hui Lin, Adam Slagell, Zbigniew Kalbarczyk, Peter W. Sauer, Ravishankar K. Iyer

2013-11-01T23:59:59.000Z

367

Delay Bounded Rate and Power Control in Energy Harvesting Wireless Networks  

E-Print Network (OSTI)

. In [3] solar energy was modeled as a Markov process after analysis of years of observed dataDelay Bounded Rate and Power Control in Energy Harvesting Wireless Networks R.A. Raghuvir and Dinesh Rajan Department of Electrical Engineering Southern Methodist University Dallas, TX 75275

Rajan, Dinesh

368

Real-Time Wind Turbine Emulator Suitable for Power Quality and Dynamic Control Studies  

E-Print Network (OSTI)

1 Real-Time Wind Turbine Emulator Suitable for Power Quality and Dynamic Control Studies Dale S. L. Dolan, Student Member, IEEE, P. W. Lehn, Member IEEE Abstract-- Wind turbines are increasingly becoming-time Wind Turbine Emulator, which emulates the dynamic torque produced by an actual turbine has been

Lehn, Peter W.

369

Individual Pitch Control for Mitigation of Power Fluctuation of Variable Speed Wind Turbines  

E-Print Network (OSTI)

, China mcheng@seu.edu.cn Abstract-- Grid connected wind turbines are the sources of power fluctuations and the individual pitch controller is designed. The simulations are performed on the NREL (National Renewable Energy shortage, great efforts have been taken around the world to implement renewable energy projects

Chen, Zhe

370

Gain Scheduled Control of a Solar Power Plant Tor A. Johansen1  

E-Print Network (OSTI)

a tube where oil is pumped through in order to collect the solar power. The control problem is to keep the temperature of the oil leaving the eld at its desired value by manipulating the oil pump ow rate. It is shown, is described. A eld of parabolic collectors focus the solar radiation onto a tube where oil is pumped through

Johansen, Tor Arne

371

Joint optimization algorithm for network reconfiguration and reactive power control of wind farm in distribution system  

Science Conference Proceedings (OSTI)

In recent years, the number of small size wind farms used as DG sources located within the distribution system are rapidly increasing. Wind farm made up with doubly fed induction generators (DFIG) is proposed in this paper as the continuous reactive ... Keywords: DFIG wind turbine, network reconfiguration, particle swarm optimization, reactive power control, wind farm

Jingjing Zhao; Xin Li; Jiping Lu; Congli Zhang

2009-02-01T23:59:59.000Z

372

Maximum Power Point Tracking Control for Photovoltaic System Using Adaptive Neuro-Fuzzy  

E-Print Network (OSTI)

converter. II. MATHEMATICAL MODELING OF PHOTOVOLTAIC CELL A PV cell can be represented by an equivalentMaximum Power Point Tracking Control for Photovoltaic System Using Adaptive Neuro- Fuzzy "ANFIS availability and vast potential, world has turned to solar photovoltaic energy to meet out its ever increasing

Recanati, Catherine

373

Rapid load following of an SOFC power system via stable fuzzy predictive tracking controller  

Science Conference Proceedings (OSTI)

The solid oxide fuel cell (SOFC) is widely accepted for clean and distributed power generation use, but critical operation problems often occur when the stand-alone fuel cell is directly connected to the electricity grid or the dc electric user. In order ... Keywords: fuel cell, fuzzy systems, identification, input-tostate stability, load following, output tracking, predictive control

Tiejun Zhang; Gang Feng

2009-04-01T23:59:59.000Z

374

A STOCHASTIC OPTIMAL CONTROL APPROACH FOR POWER MANAGEMENT IN PLUG-IN HYBRID ELECTRIC VEHICLES  

E-Print Network (OSTI)

A STOCHASTIC OPTIMAL CONTROL APPROACH FOR POWER MANAGEMENT IN PLUG-IN HYBRID ELECTRIC VEHICLES.e., the engine and electric machines) in a plug-in hybrid electric vehicle (PHEV). Existing studies focus mostly. INTRODUCTION This paper examines plug-in hybrid electric vehicles (PHEVs), i.e., automobiles that can extract

Krstic, Miroslav

375

Automated Recurrent Neural Network Design of a Neural Controller in a Custom Power Device  

Science Conference Proceedings (OSTI)

A general purpose implementation of the Tabu Search metaheuristic, called Universal Tabu Search, is used to optimally design a Locally Recurrent Neural Network architecture. Indeed, the design of a neural network is a tedious and time consuming trial ... Keywords: custom power protection device, neural controller, recurrent neural networks, universal Tabu Search

B. Cannas; G. Celli; A. Fanni; F. Pilo

2001-05-01T23:59:59.000Z

376

Nonlinear controller optimization of a power system based on reduced multivariate polynomial model  

Science Conference Proceedings (OSTI)

This paper describes the design of a nonlinear controller in a power system by using the reduced multivariate polynomial (RMP) optimization algorithm with the one-shot training property. The RMP model is applied to estimate its Hessian matrix in addition ...

Seung-Mook Baek; Jung-Wook Park

2009-06-01T23:59:59.000Z

377

Evaluation of Power Extraction to Linear Gain Scheduling Controllers in a Small Wind Energy Conversion System  

Science Conference Proceedings (OSTI)

Renewable energy sources have focused a special attention in wind energy conversion systems, where the goal is maximal power extraction. This paper presents an evaluation of the linear controllers eigen structure assingment, linear quadratic regulator, ... Keywords: Wind turbines, permanent magnet synchronous generator, eigenstructure assingment, linear quadratic regulator, loop shaping design procedure

Santiago Sanchez Acevedo; Eduardo Giraldo; Edilson Delgado Trejos

2010-09-01T23:59:59.000Z

378

Scoping Study: Surface Mount Technology and Applications in Power Electronics and Control Systems  

Science Conference Proceedings (OSTI)

The electronics packaging industry has not seen a revolution of the magnitude of surface mount technology (SMT) since the development of the printed wiring board. This study examines the rapid shift toward SMT and provides an overview of SMT applications for power electronics and controls equipment manufacturers.

1996-10-06T23:59:59.000Z

379

Reactivity estimation and validation for the control of reactor neutronic power. Master's thesis  

SciTech Connect

From July 1986 to July 1991, a joint MIT-SNL research team developed a controller capable of safely raising reactor power by approximately five orders of magnitude in a few seconds. This controller was experimentally demonstrated on the MIT Research Reactor (MITR-II) as well as on the 'Sandia National Laboratories' Annular Core Research Reactor (ACRR). This controller's intended application is for the control of spacecraft nuclear reactors. However, it also has direct application for the control of military, commercial, and research reactors. This report is concerned with a method for enhancing the controller's performance through the development of an improved model to validate estimates of the magnitude of reactivity feedback effects. The focus is on the Doppler effect but the resulting model is applicable to other types of reactivity feedback such as that associated with the thermal effects of a hydrogen coolant.

Lasota, C.S.

1993-05-01T23:59:59.000Z

380

Multidisciplinary Modeling, Control, and Optimization of a Solid Oxide Fuel Cell/Gas Turbine Hybrid Power System.  

E-Print Network (OSTI)

??This thesis describes a systematical study, including multidisciplinary modeling, simulation, control, and optimization, of a fuel cell - gas turbine hybrid power system that aims… (more)

Abbassi Baharanchi, Atid

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Voltage/Pitch Control for Maximization and Regulation of Active/Reactive Powers in Wind Turbines with Uncertainties  

E-Print Network (OSTI)

This paper addresses the problem of controlling a variable-speed wind turbine with a Doubly Fed Induction Generator (DFIG), modeled as an electromechanically-coupled nonlinear system with rotor voltages and blade pitch angle as its inputs, active and reactive powers as its outputs, and most of the aerodynamic and mechanical parameters as its uncertainties. Using a blend of linear and nonlinear control strategies (including feedback linearization, pole placement, uncertainty estimation, and gradient-based potential function minimization) as well as time-scale separation in the dynamics, we develop a controller that is capable of maximizing the active power in the Maximum Power Tracking (MPT) mode, regulating the active power in the Power Regulation (PR) mode, seamlessly switching between the two modes, and simultaneously adjusting the reactive power to achieve a desired power factor. The controller consists of four cascaded components, uses realistic feedback signals, and operates without knowledge of the C_p-...

Guo, Yi; Jiang, John N; Tang, Choon Yik; Ramakumar, Rama G

2010-01-01T23:59:59.000Z

382

Analysis of wind power for battery charging  

DOE Green Energy (OSTI)

One type of wind-powered battery charging will be explored in this paper. It consists of a wind turbine driving a permanent magnet alternator and operates at variable speed. The alternator is connected to a battery bank via a rectifier. The characteristic of the system depends on the wind turbine, the alternator, and the system configuration. If the electrical load does not match the wind turbine, the performance of the system will be degraded. By matching the electrical load to the wind turbine, the system can be improved significantly. This paper analyzes the properties of the system components. The effects of parameter variation and the system configuration on the system performance are investigated. Two basic methods of shaping the torque-speed characteristic of the generator are presented. The uncompensated as well as the compensated systems will be discussed. Control strategies to improve the system performance will be explored. Finally, a summary of the paper will be presented in the last section.

Muljadi, E.; Drouilhet, S.; Holz, R. [National Renewable Energy Lab., Golden, CO (United States); Gevorgian, V. [University of Armenia, Yerevan (Armenia). State Engineering

1995-11-01T23:59:59.000Z

383

Analysis of wind power for battery charging  

Science Conference Proceedings (OSTI)

One type of wind-powered battery charging is explored which consists of a wind turbine driving a permanent magnet alternator and which operates at variable speed. The alternator is connected to a battery bank via a rectifier. The characteristics of the system depend on the wind turbine, the alternator, and the system configuration. If the electrical load does not match the wind turbine, the performance of the system will be degraded. By matching the electrical load to the wind turbine, the system can be improved significantly. This paper analyzes the properties of the system components. The effects of parameter variation and the system configuration on the system performance are investigated. Two basic methods of shaping the torque-speed characteristic of the generator are presented. The uncompensated as well as the compensated systems are discussed. Control strategies to improve the system performance are explored.

Muljadi, E.; Drouilhet, S.; Holz, R.; Gevorgian, V.

1995-01-01T23:59:59.000Z

384

Controlled deformation of critical truss members using magnetorheological dampers with reversed power requirements  

E-Print Network (OSTI)

A magnetorheological (MR) damper exhibits a variable damping coefficient depending on the strength of an accompanying magnetic field. A high magnetic field creates a nearly unyielding damper filled with a semi-solid fluid while no magnetic field produces an ordinary viscous damper. Presently, these dampers are being used in a variety of ways by supplying power to an electromagnet that causes stiffening of the damper. Reversing these power requirements allows development of new and innovative applications for MR dampers. For example, ephemeral deformation of critical truss members may be controlled through a reverse MR damper. The goal is to provide protection to truss structures during severe loading events. Implementation of a reverse damper for an application such as this presents two major tasks: (1) development of a control algorithm and (2) design of an MR damper with reverse power requirements. A control algorithm for dynamic response that uses fuzzy logic and neural networks is presented. A potential design for a reverse MR damper utilizing a combination of permanent magnets and electromagnets is also presented. It is further shown that design for MR dampers with reverse power requirements will be governed by minimization of detrimental effects due to creep of the damper under sustained static loading.

Dowd, Joseph A

1999-01-01T23:59:59.000Z

385

Bang-bang-type optimal constant current control of parallel ac-dc power transmission systems  

SciTech Connect

The transient stability of an ac-dc hybrid system can be improved greatly by controlling the power flow of the dc transmission line. In this study the optimal changeover curve of dc current setting value on the phase plane with a quadratic curve are approximated. The coefficients of this curve are calculated in advance taking into account the loading condition of the power system and hence the proposed control scheme can be used for emergency control of the power system. The main conclusions from this study were that: to facilitate transient stability analysis, the dc transmission line is represented by equivalent load admittances, which vary every second with the operating condition of the transmission line; the action of the speed governor increases the damping coefficient of the power system and reduces the control time which means that the admissible range of the dc current setting value can be reduced by increasing the governor gain; and the optimal change-over curve of the dc current setting value is approximated by a quadratic curve, whose coefficients can be calculated in advance taking into account the loading condition of the power system. The suboptimal changeover curve thus obtained makes it possible to change the setting value of dc current without time delay in emergency condition. While the case of three-phase short-circuit fault was specifically discussed, it is possible to extend the results obtained to the case of successful or unsuccessful reclosing. The proposed method could also be applied to multimachine systems by using equivalent network reduction methods.

Kobayashi, H.; Ichiyanagi, K.

1977-01-01T23:59:59.000Z

386

Stabilizing control of parallel AC-DC power transmission systems by approximate switching curve  

SciTech Connect

A method to improve the transient stability of bulk power transmission system is presented. The method stabilizes the control of parallel ac-dc transmission systems using an approximate switching curve. The optimal switching curve is approximated by a power series and the resulting switching curve is determined independent of type and duration of faults that occur to the system. In addition, coefficients of the switching curve can be calculated on a off-line basis which allows use of simple on-line algebraic calculations in emergency conditions.

Ichiyanagi, K.; Kobayashi, H.; Kakehu, H.

1980-01-01T23:59:59.000Z

387

Modeling of integrated environmental control systems for coal-fired power plants  

SciTech Connect

The Integrated Environmental Control Model (IECM) was designed to permit the systematic evaluation of environmental control options for pulverized coal-fired (PC) power plants. Of special interest was the ability to compare the performance and cost of advanced pollution control systems to conventional'' technologies for the control of particulate, SO{sub 2} and NO{sub x}. Of importance also was the ability to consider pre-combustion, combustion and post-combustion control methods employed alone or in combination to meet tough air pollution emission standards. Finally, the ability to conduct probabilistic analyses is a unique capability of the IECM. Key results are characterized as distribution functions rather than as single deterministic values. (VC)

Rubin, E.S.; Salmento, J.S.; Frey, H.C.; Abu-Baker, A.; Berkenpas, M.

1991-05-01T23:59:59.000Z

388

Modeling of integrated environmental control systems for coal-fired power plants. Final report  

SciTech Connect

The Integrated Environmental Control Model (IECM) was designed to permit the systematic evaluation of environmental control options for pulverized coal-fired (PC) power plants. Of special interest was the ability to compare the performance and cost of advanced pollution control systems to ``conventional`` technologies for the control of particulate, SO{sub 2} and NO{sub x}. Of importance also was the ability to consider pre-combustion, combustion and post-combustion control methods employed alone or in combination to meet tough air pollution emission standards. Finally, the ability to conduct probabilistic analyses is a unique capability of the IECM. Key results are characterized as distribution functions rather than as single deterministic values. (VC)

Rubin, E.S.; Salmento, J.S.; Frey, H.C.; Abu-Baker, A.; Berkenpas, M.

1991-05-01T23:59:59.000Z

389

Nonlinear power flow feedback control for improved stability and performance of airfoil sections  

DOE Patents (OSTI)

A computer-implemented method of determining the pitch stability of an airfoil system, comprising using a computer to numerically integrate a differential equation of motion that includes terms describing PID controller action. In one model, the differential equation characterizes the time-dependent response of the airfoil's pitch angle, .alpha.. The computer model calculates limit-cycles of the model, which represent the stability boundaries of the airfoil system. Once the stability boundary is known, feedback control can be implemented, by using, for example, a PID controller to control a feedback actuator. The method allows the PID controller gain constants, K.sub.I, K.sub.p, and K.sub.d, to be optimized. This permits operation closer to the stability boundaries, while preventing the physical apparatus from unintentionally crossing the stability boundaries. Operating closer to the stability boundaries permits greater power efficiencies to be extracted from the airfoil system.

Wilson, David G.; Robinett, III, Rush D.

2013-09-03T23:59:59.000Z

390

Positron Accumulator Ring (PAR) power supply  

SciTech Connect

The Positron Accumulator Ring (PAR) consists of 8 dipole magnets connected in series. These magnets are energized via one 12-pulse dc power supply. The power supply consists of four phase controlled half-wave wye group converters. Each of the two half-wave converters are connected through an interphase transformer to obtain a full-wave converter with 120{degrees} conduction. The input voltage for these two half-wave converters are 180{degrees} apart. The two full-wave converters are connected in parallel through a third interphase transformer. This type of connection of the converters not only provides the required output current, it also improves the input power factor of the power supply. The output of the wye group converters is filtered through a passive L-R-C filter to reduce the ripple content of the output current. At low current values of the power supply the current ripple is high, thus a large filter is needed, which adds to the cost of the power supply, however at high output current levels, the current ripple is less severe. The large size of the filter can be reduced by adding an anti-parallel rectifier diode(D1) to the output of the power supply. A freewheeling diode(D2) is connected before the choke to circulate the current once the power supply is turned off. In order to measure the current in the magnet a high precision, low drift, zero flux current transductor is used. This transductor senses the magnet current which provides a feedback signal to control the gating of the converter`s thyristors. A true 14 bit Digital to Analog Converter (DAC) is programmed by the control computer for the required current value, providing a reference for the current regulator. Fast correction of the line transients is provided by a relatively fast voltage loop controlled by a high gain slow response current loop.

Fathizadeh, M.

1995-08-01T23:59:59.000Z

391

Modeling, analysis and neural MPPT control design of a PV-generator powered dc motor-pump system  

Science Conference Proceedings (OSTI)

This paper presents the optimization of a photovoltaic (PV) water pumping system using maximum power point tracking technique (MPPT). The optimization is suspended to reference optimal power. This optimization technique is developed to assure the optimum ... Keywords: artificial neural network controller, drive systems, maximum power point tracking, photovoltaic

Ahmed. M. Kassem

2011-12-01T23:59:59.000Z

392

Extended Constant Power Speed Range of the Brushless DC Motor Through Dual Mode Inverter Control  

SciTech Connect

The trapezoidal back electromotive force (emf) brushless direct current (dc) motor (BDCM) with surface-mounted magnets has high-power density and efficiency especially when rare-earth magnet materials are used. Traction applications, such as electric vehicles, could benefit significantly from the use of such motors. Unfortunately, a practical means for driving the motor over a constant power speed ratio (CPSR) of 5:1 or more has not yet been developed. A key feature of these motors is that they have low internal inductance. The phase advance method is effective in controlling the motor power over such a speed range, but the current at high speed may be several times greater than that required at the base speed. The increase in current during high-speed operation is due to the low motor inductance and the action of the bypass diodes of the inverter. The use of such a control would require increased current rating of the inverter semiconductors and additional cooling for the inverter, where the conduction losses increase proportionally with current, and especially for the motor, where the losses increase with the square of the current. The high current problems of phase advance can be mitigated by adding series inductance; however, this reduces power density, requires significant increase in supply voltage, and leaves the CPSR performance of the system highly sensitive to variations in the available voltage. A new inverter topology and control scheme has been developed that can drive low-inductance BDCMs over the CPSR that would be required in electric vehicle applications. This new controller is called the dual-mode inverter control (DMIC). It is shown that the BDCM has an infinite CPSR when it is driven by the DMIC.

Lawler, J.S.

2000-06-23T23:59:59.000Z

393

Operational, control and protective system transient analyses of the closed-cycle GT-HTGR power plant  

SciTech Connect

This paper presents a description of the analyses of the control/protective system preliminary designs for the gas turbine high-temperature gas-cooled reactor (GT-HTGR) power plant. The control system is designed to regulate reactor power, control electric load and turbine speed, control the temperature of the helium delivered to the turbines, and control thermal transients experienced by the system components. In addition, it provides the required control programming for startup, shutdown, load ramp, and other expected operations. The control system also handles conditions imposed on the system during upset and emergency conditions such as loop trip, reactor trip, or electrical load rejection.

Openshaw, F.L.; Chan, T.W.

1980-07-01T23:59:59.000Z

394

TPX power systems design overview  

SciTech Connect

The power systems for the Tokamak Physics Experiment (TPX) supply the Toroidal Field (TF). Poloidal Field (PF), Field Error Correction (FEC), and Fast Vertical Position Control (FVPC) coil systems, the Neutral Beam (NB), Ion Cyclotron (IC), Lower Hybrid (LH) and Electron Cyclotron (EC) heating and current drive systems, and all balance of plant loads. Existing equipment from the Tokamak Fusion Test Reactor (TFTR), including the motor-generator (MG) sets and the rectifiers, can be adapted for the supply of the TPX PF systems. A new TF power supply is required. A new substation is required for the heating and current drive systems (NB, IC, LH, and EC). The baseline TPX load can be taken directly from the grid without special provision, whereas if all upgrade options are undertaken, a modest amount of reactive compensation will be required. This paper describes the conceptual design of the power systems, with emphasis on the AC, TF, and PF Systems, and the quench protection of the superconducting coils.

Neumeyer, C. [Ebasco Services, Inc., New York, NY (United States); Bronner, G.; Lu, E.; Ramakrishnan, S. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Jackson, M. [Lawrence Livermore National Lab., CA (United States)

1993-11-01T23:59:59.000Z

395

A Distributed Power Control and Transmission Rate Allocation Algorithm over Multiple Channels  

E-Print Network (OSTI)

In this paper, we consider multiple channels and wireless nodes with multiple transceivers. Each node assigns one transmitter at each available channel. For each assigned transmitter the node decides the power level and data rate of transmission in a distributed fashion, such that certain Quality of Service (QoS) demands for the wireless node are satisfied. More specifically, we investigate the case in which the average SINR over all channels for each communication pair is kept above a certain threshold. A joint distributed power and rate control algorithm for each transmitter is proposed that dynamically adjusts the data rate to meet a target SINR at each channel, and to update the power levels allowing for variable desired SINRs. The algorithm is fully distributed and requires only local interference measurements. The performance of the proposed algorithm is shown through illustrative examples.

Charalambous, Themistoklis

2011-01-01T23:59:59.000Z

396

An ultra low-power digitally-controlled buck converter IC for cellular phone applications  

E-Print Network (OSTI)

Abstract — This paper describes a dual-mode digitallycontrolled buck converter IC for cellular phone applications. An architecture employing internal power management is introduced to ensure voltage compatibility between a singlecell lithium-ion battery voltage and a low voltage integrated circuit technology. Special purpose analog and digital interface elements are developed. These include a ring-oscillator based ADC (ring-ADC), which is nearly entirely synthesizable, robust against switching noise, and has flexible resolution control, and a very low power ring oscillator-multiplexer based Digital PWM generation module (ring-MUX DPWM). The chip, which includes an output power stage rated for 400 mA, occupies 2mm 2 active area in 0.25-µm CMOS. Very high efficiencies are achieved over a load range of 0.1 to 400 mA. Measured quiescent current in PFM mode is 4 µA. I.

Jinwen Xiao; Angel Peterchev; Jianhui Zhang; Seth Sanders

2004-01-01T23:59:59.000Z

397

A low-power circuit for piezoelectric vibration control by synchronized switching on voltage sources  

E-Print Network (OSTI)

In the paper, a vibration damping system powered by harvested energy with implementation of the so-called SSDV (synchronized switch damping on voltage source) technique is designed and investigated. In the semi-passive approach, the piezoelectric element is intermittently switched from open-circuit to specific impedance synchronously with the structural vibration. Due to this switching procedure, a phase difference appears between the strain induced by vibration and the resulting voltage, thus creating energy dissipation. By supplying the energy collected from the piezoelectric materials to the switching circuit, a new low-power device using the SSDV technique is proposed. Compared with the original self-powered SSDI (synchronized switch damping on inductor), such a device can significantly improve its performance of vibration control. Its effectiveness in the single-mode resonant damping of a composite beam is validated by the experimental results.

Shen, Hui; Ji, Hongli; Zhu, Kongjun; Balsi, Marco; Giorgio, Ivan; dell'Isola, Francesco

2010-01-01T23:59:59.000Z

398

Loss of integrated control system power and overcooling transient at Rancho Seco on December 26, 1985  

Science Conference Proceedings (OSTI)

On December 26, 1985, Rancho Seco Nuclear Generating Station, located in Clay, California, about 25 miles southeast of Sacramento, experienced a loss of dc power within the integrated control system (ICS) while the plant was operating at 76% power. The plant is owned by the Sacramento Municipal Utility District (SMUD). Following the loss of ICS dc power, the reactor tripped on high reactor coolant system (RCS) pressure followed by a rapid overcooling transient and automatic initiation of the safety features actuation system on low RCS pressure. The overcooling transient continued until ICS dc power was restored 26 minutes after its loss. The fundamental causes for this transient were design weaknesses and vulnerabilities in the ICS and in the equipment controlled by that system. These weaknesses and vulnerabilities were not adequately compensated by other design features, plant procedures or operator training. These weaknesses and vulnerabilities were largely known to SMUD and the NRC staff by virtue of a number of precursor events and through related analyses and studies. Yet, adequate plant modifications were not made so that this event would be improbable, or so that its course or consequences would be altered significantly. The information was available and known which could have prevented this overcooling transient; but in the absence of adequate plant modifications, the incident should have been expected. The report includes findings and conclusions of the NRC Incident Investigation Team sent to Rancho Seco by the NRC Executive Director for Operations in conformance with NRC's recently established Incident Investigation Program. 33 figs.

Not Available

1986-02-01T23:59:59.000Z

399

Identification of Critical Voltage Control Areas and Determination of Required Reactive Power Reserves  

Science Conference Proceedings (OSTI)

This Technical Update reports on the development of a highly automated method for identifying Voltage Control Areas (VCAs), areas prone to voltage instability in practical power system models. For a wide range of system conditions and contingencies, the technique can identify the buses in each VCA and identify VCAs that are common for a set of contingencies and/or conditions. In addition, the method identifies the generators that are critical to maintaining stability for a given VCA. The methods develope...

2007-09-24T23:59:59.000Z

400

Multiple boiler steam blending control system for an electric power plant  

SciTech Connect

A steam blending control is provided for two or more boilers in an electric power plant. To blend an oncoming boiler with an online boiler, the oncoming boiler is fired to a pressure ramp setpoint and outlet steam is isolated from the plant turbine and directed through position controlled bypass valve means. When steam temperature and pressure conditions are matched, the oncoming boiler isolation valve is opened and the bypass flow then existing is stored in a memory. The oncoming boiler bypass flow is cut back with total oncoming boiler steam flow controlled to the memorized flow valve as a setpoint. Flow from the on-line boiler is cut back under load control as the oncoming boiler flow to the plant turbine is increased. Deblending is implemented in a similar manner.

Binstock, M.H.; Criswell, R.L.

1981-12-22T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Performance-Aware Power Management in Embedded Controllers with Multiple-Voltage Processors  

E-Print Network (OSTI)

The goal of this work is to minimize the energy dissipation of embedded controllers without jeopardizing the quality of control (QoC). Taking advantage of the dynamic voltage scaling (DVS) technology, this paper develops a performance-aware power management scheme for embedded controllers with processors that allow multiple voltage levels. The periods of control tasks are adapted online with respect to the current QoC, thus facilitating additional energy reduction over standard DVS. To avoid the waste of CPU resources as a result of the discrete voltage levels, a resource reclaiming mechanism is employed to maximize the CPU utilization and also to improve the QoC. Simulations are conducted to evaluate the performance of the proposed scheme. Compared with the optimal standard DVS scheme, the proposed scheme is shown to be able to save remarkably more energy while maintaining comparable QoC.

Xia, Feng; Ma, Longhua; Sun, Youxian; Dong, Jinxiang

2008-01-01T23:59:59.000Z

402

Photovoltaic power converter system with a controller configured to actively compensate load harmonics  

DOE Patents (OSTI)

Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.

de Rooij, Michael Andrew (Clifton Park, NY); Steigerwald, Robert Louis (Burnt Hills, NY); Delgado, Eladio Clemente (Burnt Hills, NY)

2008-12-16T23:59:59.000Z

403

Assessment of H/sub 2/S control technologies for geothermal power plants  

DOE Green Energy (OSTI)

Techniques for controlling hydrogen sulfide (H/sub 2/S) from geothermal development are analyzed. Several technologies for controlling H/sub 2/S emissions from power plants are examined. The Hydrogen Peroxide Combination System, Stretford System and possibly EIC or Coury upstream controls appear capable of compliance with the emission limitations of 100 grams per hour per gross megawatt in 1980 (and 50 q/hr/(g) MW in 1985 or 1990) at the Geysers Dry stream field in Northern California. Unresolved problems still plague all these options. Well field operations result in H/sub 2/S releases from well drilling, well venting and steam stacking. Hydrogen peroxide reduces H/sub 2/S emissions during drilling and venting can be controlled with vent gathering (condensation/reinjection) systems. Steam stacking during power plant outages emit more H/sub 2/S over shorter periods than other field operations. Potential controls for stacking are: (1) upstream abatement, (2) automated well operation, (3) computerized wellfield operation (as of PG and E's Geysers Unit No. 15), and (4) further steamfield interconnection (cross-overs).

Not Available

1980-02-01T23:59:59.000Z

404

Cooldown control system for a combined cycle electrical power generation plant  

SciTech Connect

This patent describes a combined cycle electrical power plant including a steam turbine, a heat recovery steam generator for supplying steam to the steam turbine, a gas turbine for supplying heat to the heat recovery steam generator. The steam generator and gas turbine both produce electrical power under load, and the gas turbine has a control circuit determining the operation therof. A cooldown control system is described for the power generation plant. The system comprises: first means for detecting one of a steaming condition and a non-steaming condition in the heat recovery steam generator; second means responsive to the steaming condition and to a gas turbine STOP signal for reducing the load of the gas turbine toward a minimum load level; third means responsive to the non-steaming condition and to the minimum load level being reached for generating a STOP command and applying the STOP command to the control circuit of the gas turbine, thereby to indicate a sequence of steps to stop the gas turbine.

Martens, A.; Snow, B.E.

1987-01-27T23:59:59.000Z

405

Towards More Flexible and Robust Data Delivery for Monitoring and Control of the Electric Power Grid  

E-Print Network (OSTI)

URL for this paper: www.gridstat.net/TR-GS-009.pdf Abstract—With the increase in the monitoring of status data at very high rates in high voltage substations and the ability to time synchronize these data with GPS signals, there is a growing need for transmitting this data for monitoring, operation, protection and control needs. The sets of data that need to be transferred and the speed at which they need to be transferred depend on the application – for example, slow for post-event analysis, near real-time for monitoring and as close to real-time as possible for control or protection. In this paper, we overview the requirements for the next-generation power grid’s communication infrastructure in the areas of flexibility and quality of service, with extensive citations of power industry practitioners and researchers, and analyze implementation options. We also overview technologies in the computer science field of distributed computing that can be brought to bear to help meet these requirements, yet to date have not been discussed in the context of grid modernization. Additionally, we argue against the industry trend of using either TCP/IP or web services for real-time data exchange for fast controls. We then describe GridStat, a novel middleware framework we have developed that is suitable for the power grid and its application programs. Test results demonstrate that such a flexible framework can also guarantee

David E. Bakken; Carl H. Hauser; Harald Gjermundrřd; Anjan Bose

2007-01-01T23:59:59.000Z

406

Gate-turn-off thyristors provide new level of power-flow control  

SciTech Connect

The availability of high-power, gate-turn-off (GTO) thyristors has made possible the development of a new class of solid-state devices that promise an unprecedented degree of control over the flow of power in the nation`s network. The first of these, a static compensator known as Statcom, which offers dynamic control over the flow of VArs into, or out of, the network, was unveiled last month at the Tennessee Valley Authority`s (TVA) Sullivan substation in eastern Tennessee. The principal element of the Statcom is a voltage-sourced inverter that converts dc voltage at its input terminals into a 3-phase alternating output voltage. To eliminate the quasi square wave that a single inverter would generate - along with unacceptable harmonics - the Statcom uses many such inverters, appropriately phase-shifted, and combines their outputs through electromagnetic linkages to produce a nearly sinusoidal output waveform. By numerous voltage additions and subtractions, eight inverters used in the Statcom generate a 48-pulse, nearly sinusoidal output waveform. The GTO-based inverters and electronic feedback control give the Statcom a dynamic performance far exceeding that of other reactive power compensators. In fact, the device can transition from full rated capacitive to full-rated VArs in approximately one-quarter cycle. Nominal rating of each inverter is 12.5 MVA. 12 figs.

NONE

1995-12-01T23:59:59.000Z

407

Heat recovery steam generator outlet temperature control system for a combined cycle power plant  

Science Conference Proceedings (OSTI)

This patent describes a command cycle electrical power plant including: a steam turbine and at least one set comprising a gas turbine, an afterburner and a heat recovery steam generator having an attemperator for supplying from an outlet thereof to the steam turbine superheated steam under steam turbine operating conditions requiring predetermined superheated steam temperature, flow and pressure; with the gas turbine and steam turbine each generating megawatts in accordance with a plant load demand; master control means being provided for controlling the steam turbine and the heat recovery steam generator so as to establish the steam operating conditions; the combination of: first control means responsive to the gas inlet temperature of the heat recovery steam generator and to the plant load demand for controlling the firing of the afterburner; second control means responsive to the superheated steam predetermined temperature and to superheated steam temperature from the outlet for controlling the attemperator between a closed and an open position; the first and second control means being operated concurrently to maintain the superheated steam outlet temperature while controlling the load of the gas turbine independently of the steam turbine operating conditions.

Martens, A.; Myers, G.A.; McCarty, W.L.; Wescott, K.R.

1986-04-01T23:59:59.000Z

408

Stability effects of frequency controllers and transmission line configurations on power systems with integration of wind power  

E-Print Network (OSTI)

This thesis investigates the stability effects of the integration of wind power on multi-machine power systems. First, the small-signal stability effects of turbine governors connected to synchronous generators in the ...

Abdelhalim, Hussein Mohamed

2012-01-01T23:59:59.000Z

409

A New 4H-SiC Lateral Merged Double Schottky (LMDS) Rectifier With Excellent Forward and Reverse Characteristics  

E-Print Network (OSTI)

The novel characteristics of a new Schottky rectifier structure, known as the lateral merged double Schottky (LMDS) rectifier, on 4H-SiC are explored theoretically and compared with those of the compatible conventional 4H-SiC Schottky rectifiers. The anode of the proposed lateral device utilizes the trenches filled with a high barrier Schottky (HBS) metal to pinch off a low barrier Schottky (LBS) contact during reverse bias. Numerical simulation of any such SiC structure is complicated by the fact that the thermionic emission theory predicts the reverse leakage current to be orders of magnitude smaller than the measured data. We, therefore, first propose a simple empirical model for barrier height lowering to accurately estimate the reverse leakage current in a SiC Schottky contact. The accuracy of the empirical model is verified by comparing the simulated reverse leakage current with the reported experimental results on different SiC Schottky structures. Using the proposed empirical model, the two-dimensional (2-D) numerical simulations reveal that the new LMDS rectifier demonstrates about three orders of magnitude reduction in the reverse leakage current and two times higher reverse breakdown voltage when compared to the conventional lateral low barrier Schottky (LLBS) rectifier while keeping the forward voltage drop comparable to that of the conventional LLBS rectifier. A unique feature of the 4H-SiC LMDS rectifier is that it exhibits a very sharp PiN diode-like reverse blocking characteristic in spite of the fact that only Schottky junctions are used in the structure. The reasons for the improved performance of the LMDS rectifier are analyzed and design tradeoff between the forward voltage drop and the reverse leakage current is provided by varying the device parame...

Yashvir Singh And; Yashvir Singh; M. Jagadesh Kumar; Senior Member

2001-01-01T23:59:59.000Z

410

Applying Human Factors Evaluation and Design Guidance to a Nuclear Power Plant Digital Control System  

SciTech Connect

The United States (U.S.) nuclear industry, like similar process control industries, has moved toward upgrading its control rooms. The upgraded control rooms typically feature digital control system (DCS) displays embedded in the panels. These displays gather information from the system and represent that information on a single display surface. In this manner, the DCS combines many previously separate analog indicators and controls into a single digital display, whereby the operators can toggle between multiple windows to monitor and control different aspects of the plant. The design of the DCS depends on the function of the system it monitors, but revolves around presenting the information most germane to an operator at any point in time. DCSs require a carefully designed human system interface. This report centers on redesigning existing DCS displays for an example chemical volume control system (CVCS) at a U.S. nuclear power plant. The crucial nature of the CVCS, which controls coolant levels and boration in the primary system, requires a thorough human factors evaluation of its supporting DCS. The initial digital controls being developed for the DCSs tend to directly mimic the former analog controls. There are, however, unique operator interactions with a digital vs. analog interface, and the differences have not always been carefully factored in the translation of an analog interface to a replacement DCS. To ensure safety, efficiency, and usability of the emerging DCSs, a human factors usability evaluation was conducted on a CVCS DCS currently being used and refined at an existing U.S. nuclear power plant. Subject matter experts from process control engineering, software development, and human factors evaluated the DCS displays to document potential usability issues and propose design recommendations. The evaluation yielded 167 potential usability issues with the DCS. These issues should not be considered operator performance problems but rather opportunities identified by experts to improve upon the design of the DCS. A set of nine design recommendations was developed to address these potential issues. The design principles addressed the following areas: (1) color, (2) pop-up window structure, (3) navigation, (4) alarms, (5) process control diagram, (6) gestalt grouping, (7) typography, (8) terminology, and (9) data entry. Visuals illustrating the improved DCS displays accompany the design recommendations. These nine design principles serve as the starting point to a planned general DCS style guide that can be used across the U.S. nuclear industry to aid in the future design of effective DCS interfaces.

Thomas Ulrich; Ronald Boring; William Phoenix; Emily Dehority; Tim Whiting; Jonathan Morrell; Rhett Backstrom

2012-08-01T23:59:59.000Z

411

Method of and apparatus for controlling loads on an electrical power supply  

SciTech Connect

To enable a consumer of electrical energy to effect control of total energy consumption by various individual appliances and loads, each individual load has a control unit, conveniently in a plug top, which responds to pulses broadcast on the power supply wiring in the form of short duration interruptions of the waveform. At each appliance a microprocessor unit counts the number of successive pulses in a predetermined time interval and operates an electronic switch if the received count reaches a predetermined number, which may be different for different loads thereby enabling selective control of the loads. Provision is made for automatic restoration of supply if the overall energy consumption falls. Provision can also be made for automatic resumption of supp

Peddie, R.A.; Fielden, J.S.

1984-09-11T23:59:59.000Z

412

Energy-Efficient Power Control in Multipath CDMA Channels via Large System Analysis  

E-Print Network (OSTI)

This paper is focused on the design and analysis of power control procedures for the uplink of multipath code-division-multiple-access (CDMA) channels based on the large system analysis (LSA). Using the tools of LSA, a new decentralized power control algorithm aimed at energy efficiency maximization and requiring very little prior information on the interference background is proposed; moreover, it is also shown that LSA can be used to predict with good accuracy the performance and operational conditions of a large network operating at the equilibrium over a multipath channel, i.e. the power, signal-to-interference-plus-noise ratio (SINR) and utility profiles across users, wherein the utility is defined as the number of bits reliably delivered to the receiver for each energy-unit used for transmission. Additionally, an LSA-based performance comparison among linear receivers is carried out in terms of achieved energy efficiency at the equilibrium. Finally, the problem of the choice of the utility-maximizing tr...

Buzzi, Stefano; Poor, H Vincent

2008-01-01T23:59:59.000Z

413

Distributed control of reactive power flow in a radial distribution circuit with high photovoltaic penetration  

SciTech Connect

We show how distributed control of reactive power can serve to regulate voltage and minimize resistive losses in a distribution circuit that includes a significant level of photovoltaic (PV) generation. To demonstrate the technique, we consider a radial distribution circuit with a single branch consisting of sequentially-arranged residential-scale loads that consume both real and reactive power. In parallel, some loads also have PV generation capability. We postulate that the inverters associated with each PV system are also capable of limited reactive power generation or consumption, and we seek to find the optimal dispatch of each inverter's reactive power to both maintain the voltage within an acceptable range and minimize the resistive losses over the entire circuit. We assume the complex impedance of the distribution circuit links and the instantaneous load and PV generation at each load are known. We compare the results of the optimal dispatch with a suboptimal local scheme that does not require any communication. On our model distribution circuit, we illustrate the feasibility of high levels of PV penetration and a significant (20% or higher) reduction in losses.

Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory; Sule, Petr [NEW MEXICO CONSORTIUM

2009-01-01T23:59:59.000Z

414

Distributed control of reactive power flow in a radial distribution circuit with high photovoltaic penetration  

SciTech Connect

We show how distributed control of reactive power can serve to regulate voltage and minimize resistive losses in a distribution circuit that includes a significant level of photovoltaic (PV) generation. To demonstrate the technique, we consider a radial distribution circuit with a single branch consisting of sequentially-arranged residential-scale loads that consume both real and reactive power. In parallel, some loads also have PV generation capability. We postulate that the inverters associated with each PV system are also capable of limited reactive power generation or consumption, and we seek to find the optimal dispatch of each inverter's reactive power to both maintain the voltage within an acceptable range and minimize the resistive losses over the entire circuit. We assume the complex impedance of the distribution circuit links and the instantaneous load and PV generation at each load are known. We compare the results of the optimal dispatch with a suboptimal local scheme that does not require any communication. On our model distribution circuit, we illustrate the feasibility of high levels of PV penetration and a significant (20% or higher) reduction in losses.

Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory; Sule, Petr [NEW MEXICO CONSORTIUM

2009-01-01T23:59:59.000Z

415

Using System Dynamics to Define, Study, and Implement Smart Control Strategies on the Electric Power Grid  

DOE Green Energy (OSTI)

The United States electric power grid is the most complex and expansive control system in the world. Local generation control occurs at individual units based on response time and unit economics, larger regional control coordinates unit response to error conditions, and high level large-area regional control is ultimately administered by a network of humans guided by economic and resiliency related factors. Under normal operating conditions, the grid is a relatively slow moving entity that exhibits high inertia to outside stimuli, and behaves along repeatable diurnal and seasonal patterns. However, that paradigm is quickly changing because of the increasing implementation of renewable generation sources. Renewable generators by nature cannot be tightly controlled or scheduled. They appear like a negative load to the system with all of the variability associated with load on a larger scale. Also, grid-reactive loads (i.e. smart devices) can alter their consumption based on price or demand rules adding more variability to system behavior. This paper demonstrates how a systems dynamic modeling approach capable of operating over multiple time scales, can provide valuable insight into developing new “smart-grid” control strategies and devices needed to accommodate renewable generation and regulate the frequency of the grid.

Lyle G. Roybal; Robert F Jeffers

2013-07-01T23:59:59.000Z

416

Method of installing a control room console in a nuclear power plant  

DOE Patents (OSTI)

An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board (24) is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof.

Scarola, Kenneth (Windsor, CT); Jamison, David S. (Windsor, CT); Manazir, Richard M. (North Canton, CT); Rescorl, Robert L. (Vernon, CT); Harmon, Daryl L. (Enfield, CT)

1994-01-01T23:59:59.000Z

417

A Multi-Pollutant Framework for Evaluating CO2 Control Options for Fossil Fuel Power Plants  

NLE Websites -- All DOE Office Websites (Extended Search)

Multi-Pollutant Framework for Evaluating CO Multi-Pollutant Framework for Evaluating CO 2 Control Options for Fossil Fuel Power Plants Edward S. Rubin (rubin@cmu.edu; 412-268-5897) Anand B. Rao (abr@andrew.cmu.edu; 412-268-5605) Michael B. Berkenpas (mikeb@cmu.edu; 412-268-1088) Carnegie Mellon University EPP Department, Baker Hall 128A Pittsburgh, PA 15213 Abstract As part of DOE/NETL's Carbon Sequestration Program, we are developing an integrated, multi-pollutant modeling framework to evaluate the costs and performance of alternative carbon capture and sequestration technologies for fossil-fueled power plants. The model calculates emissions, costs, and efficiency on a systematic basis at the level of an individual plant or facility. Both new and existing facilities can be modeled, including coal-based or natural gas-based combustion or gasification systems using air or oxygen.

418

ASSESSMENT OF LOW COST NOVEL SORBENTS FOR COAL-FIRED POWER PLANT MERCURY CONTROL  

Science Conference Proceedings (OSTI)

This is a Technical Report under a program funded by the Department of Energy's National Energy Technology Laboratory (NETL) to obtain the necessary information to assess the viability of lower cost alternatives to commercially available activated carbon for mercury control in coal-fired utilities. During this reporting period, several sorbent samples have been tested by URS in their laboratory fixed-bed system. The sorbents were evaluated under conditions simulating flue gas from power plants burning Powder River Basin (PRB) and low sulfur eastern bituminous coals. The equilibrium adsorption capacities of the sorbents for both elemental and oxidized mercury are presented. A team meeting discussing the overall program and meetings with Midwest Generation and Wisconsin Electric Power Company (WEPCO) concerning field testing occurred during this reporting period.

Sharon Sjostrom

2002-02-22T23:59:59.000Z

419

Modeling, Control and Maximum Power Point Tracking (MPPT) of Doubly-fed Induction Generator (DFIG) Wind Power System.  

E-Print Network (OSTI)

??Wind power is the fastest growing renewable energy and is promising to be the number one source of clean energy in the near future. Among… (more)

Zou, Yu

2012-01-01T23:59:59.000Z

420

The Evaluation of Mercury Emissions and Control Options for Ontario Power Generation Nanticoke Station  

Science Conference Proceedings (OSTI)

Canada-wide standards for mercury are being developed, and draft requirements will likely be available in 2002 (with a revised version by 2005) for potential implementation in the 2007 to 2010 period. Mercury emissions from coal-fired power plants are also likely to be subjected to regulatory control. The U.S. Environmental Protection Agency (EPA) is developing proposed mercury regulations and plans to issue final regulations on mercury emissions from coal-fired boilers by December 15, 2004 for full comp...

2002-08-13T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Deaerator pressure control system for a combined cycle steam generator power plant  

Science Conference Proceedings (OSTI)

In a combined cycle steam generation power plant, until steam extraction can be used to reheat the deaerator, the economizer and/or the pegging recirculation are controlled so as to track the pressure upwards of the autocirculation reheater from the low pressure evaporator with a certain lag in pressure, and to establish pressure in the deaerator on the decreasing trend of the autocirculation reheater at a slower rate and without lowering below a minimum pressure so as to prevent the occurrence of bubbling and cavitation effect.

Martens, A.; Myers, G. A.

1985-12-03T23:59:59.000Z

422

Control system design for maintaining CO{sub 2} capture in IGCC power plants while loading-following  

SciTech Connect

Load-following requirements for future integrated gasification combined cycle (IGCC) power plants with precombustion CO{sub 2} capture are expected to be far more challenging as electricity produced by renewable energy is connected to the grid and strict environmental limits become mandatory requirements. In this work, loadfollowing studies are performed using a comprehensive dynamic model of an IGCC plant with pre-combustion CO{sub 2} capture developed in Aspen Engineering Suite (AES). Considering multiple single-loop controllers for power demand load following, the preferred IGCC control strategy from the perspective of a power producer is gas turbine (GT) lead with gasifier follow. In this strategy, the GT controls the load by manipulating its firing rate while the slurry feed flow to the gasifier is manipulated to control the syngas pressure at the GT inlet. The syngas pressure control is an integrating process with significant time delay mainly because of the large piping and equipment volumes between the gasifier and the GT inlet. A modified proportional–integral–derivative (PID) control is considered for IGCC syngas pressure control. The desired CO{sub 2} capture rate must be maintained while the IGCC plant follows the load. For maintaining the desired CO{sub 2} capture rate, the control performance of PID control is compared with linear model predictive control (LMPC). The results show that the LMPC outperforms PID control for maintaining CO{sub 2} capture rates in an IGCC power plant while load following.

Bhattacharyya, D.; Turton, R.; Zitney, S.

2012-01-01T23:59:59.000Z

423

Assessment of Retro-Fit Energy Savings Devices: Power Efficiency Corporation's Three-Phase Motor Efficiency Controller  

Science Conference Proceedings (OSTI)

This report describes and documents the energy savings and power quality results of testing performed on Power Efficiency Corporation's Motor Efficiency Controller (MEC). The MEC is designed with patented E-Save Technology to help increase motor efficiency at low load levels, which in turn will introduce energy savings for the customer. Testing includes efficiency testing from an unloaded state to 100% load and power quality testing, such as sags and sustained undervoltage. The objectives of this project...

2010-07-08T23:59:59.000Z

424

The design of a controllable energy recovery device for solar powered reverse osmosis desalination with experimental validation  

E-Print Network (OSTI)

The purpose of this thesis is to design and validate a controllable energy recovery device with application to photovoltaic powered reverse osmosis (PVRO). The energy consumption of a reverse osmosis plant depends significantly ...

Reed, Elizabeth Anne, S.M. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

425

Nitrogen Isotopic Composition of Coal-Fired Power Plant NOx: Influence of Emission Controls and Implications for Global Emission  

E-Print Network (OSTI)

Nitrogen Isotopic Composition of Coal-Fired Power Plant NOx: Influence of Emission Controls from coal-fired power plants in the U.S. at typical operating conditions with and without the presence this, a novel method for collection and isotopic analysis of coal-fired stack NOx emission samples

Elliott, Emily M.

426

Operation and control of space-based solar energy power plants with CCGT using helium as a working medium  

Science Conference Proceedings (OSTI)

The features of a Space-based Solar Energy Power Plant for electric power generation with a closed cycle gas turbine running on Helium are discussed. The system is intended for generating both electricity and process heat for industrial manufacturing processes in a large space station. A system overview for operation and control of such a plant is presented.

Sutsch, A.

1986-01-01T23:59:59.000Z

427

Combined cycle electric power plant with coordinated steam load distribution control  

SciTech Connect

A combined cycle electric power plant includes gas and steam turbines and a steam generator for recovering the heat in the exhaust gases exited from the gas turbine and for using the recovered heat to produce and supply steam to the steam turbine. The steam generator includes a superheater tube through which a fluid, e.g., water, is directed to be additionally heated into superheated steam by the exhaust gas turbine gases. An afterburner further heats the exhaust gas turbine gases passed to the superheater tube. The temperature of the gas turbine exhaust gases is sensed for varying the fuel flow to the afterburner by a fuel valve, whereby the temperatures of the gas turbine exhaust gases and therefore of the superheated steam, are controlled. Loading and unloading of the steam turbine is accomplished automatically in coordinated plant control as a function of steam throttle pressure.

Uram, R.

1979-09-25T23:59:59.000Z

428

Digital control systems in nuclear power plants: Failure information, modeling concepts, and applications. Revision 1  

SciTech Connect

This report briefly describes some current applications of advanced computerized digital display and control systems at US commercial nuclear power plants and presents the results of a literature search that was made to gather information on the reliability of these systems. Both hardware and software reliability were addressed in this review. Only limited failure rate information was found, with the chemical process industry being the primary source of information on hardware failure rates and expert opinion the primary source for software failure rates. Safety-grade digital control systems are typically installed on a functional like-for-like basis, replacing older analog systems without substantially changing interactions with other plant systems. Future work includes performing a limited probabilistic risk assessment of a representative DCS to assess its risk significance.

Galyean, W.J.

1993-06-23T23:59:59.000Z

429

Power Supplies for Precooler Ring  

SciTech Connect

Eight power supplies will energize the antiproton Precooler ring. there will be two series connected supplies per quadrant. These supplies will power 32 dipole and 19 quadrupole magnets. The resistance and inductance per quadrant is R = 1.4045 Ohms and L = 0.466. Each powr supply will have 12-phase series bridge rectifiers and will be energized from the 480 V 3-phase grid. The total of eight power supplies are numbered IA, IIA, IIIA, IVA, and IB, IIB, IIIB, and IVB. Each quadrant will contain one A and one B supply. A block diagram of the Precooler ring with its power supplies is shown in Figure 1.

Fuja, Raymond; Praeg, Walter

1980-12-12T23:59:59.000Z

430

AC Resonant charger with charge rate unrelated to primary power frequency  

DOE Patents (OSTI)

An AC resonant charger for a capacitive load, such as a PFN, is provided with a variable repetition rate unrelated to the frequency of a multi-phase AC power source by using a control unit to select and couple the phase of the power source to the resonant charger in order to charge the capacitive load with a phase that is the next to begin a half cycle. For optimum range in repetition rate and increased charging voltage, the resonant charger includes a step-up transformer and full-wave rectifier. The next phase selected may then be of either polarity, but is always selected to be of a polarity opposite the polarity of the last phase selected so that the transformer core does not saturate. Thyristors are used to select and couple the correct phase just after its zero crossover in response to a sharp pulse generated by a zero-crossover detector. The thyristor that is turned on then automatically turns off after a full half cycle of its associated phase input. A full-wave rectifier couples the secondary winding of the transformer to the load so that the load capacitance is always charged with the same polarity.

Watson, Harold (Torrance, CA)

1982-01-01T23:59:59.000Z

431

Ac resonant charger with charge rate unrelated to preimary power requency  

DOE Patents (OSTI)

An ac resonant charger for a capacitive load, such as a pulse forming network (PFN), is provided with a variable repetition rate unrelated to the frequency of a multi-phase ac power source by using a control unit to select and couple the phase of the power source to the resonant charger in order to charge the capacitive load with a phase that is the next to begin a half cycle. For optimum range in repetition rate and increased charging voltage, the resonant charger includes a step-up transformer and full-wave rectifier. The next phase selected may then be of either polarity, but is always selected to be of a polarity opposite the polarity of the last phase selected so that the transformer core does not saturate. Thyristors are used to select and couple the correct phase just after its zero crossover in response to a sharp pulse generated by a zero-crossover detector. The thyristor that is turned on then automatically turns off after a full half cycle of its associated phase input. A full-wave rectifier couples the secondary winding of the transformer to the load so that the load capacitance is always charged with the same polarity.

Not Available

1979-12-07T23:59:59.000Z

432

A control system for improved battery utilization in a PV-powered peak-shaving system  

SciTech Connect

Photovoltaic (PV) power systems offer the prospect of allowing a utility company to meet part of the daily peak system load using a renewable resource. Unfortunately, some utilities have peak system- load periods that do not match the peak production hours of a PV system. Adding a battery energy storage system to a grid-connected PV power system will allow dispatching the stored solar energy to the grid at the desired times. Batteries, however, pose system limitations in terms of energy efficiency, maintenance, and cycle life. A new control system has been developed, based on available PV equipment and a data acquisition system, that seeks to minimize the limitations imposed by the battery system while maximizing the use of PV energy. Maintenance requirements for the flooded batteries are reduced, cycle life is maximized, and the battery is operated over an efficient range of states of charge. This paper presents design details and initial performance results on one of the first installed control systems of this type.

Palomino, E [Salt River Project, Phoenix, AZ (United States); Stevens, J. [Sandia National Labs., Albuquerque, NM (United States); Wiles, J. [New Mexico State Univ., Las Cruces, NM (United States). Southwest Technology Development Inst.

1996-08-01T23:59:59.000Z

433

Controlling Market Power and Price Spikes in Electricity Networks: Demand-side Bidding  

E-Print Network (OSTI)

Simona Lup, Jia Jing Liu and Stephen Sosnicki for help with running the experiments and testing the software. This paper has benefited from comments from Kevin McCabe, Mark Olson, Dave Porter, and Stan Reynolds, but all errors are our own. The data are available upon request from the authors. Controlling Market Power and Price Spikes in Electricity Networks: Demand-Side Bidding In this paper we report experiments that examine how two structural features of electricity networks contribute to the exercise of market power in deregulated markets. The first feature is the distribution of ownership of a given set of generating assets. In the market power treatment, two large firms are allocated baseload and intermediate cost generators such that either firm might unilaterally withhold the capacity of its intermediate cost generators from the market to benefit from the supracompetitive prices that would result from only selling its baseload units. In the converse treatment, ownership of some of the intermediate cost generators is transferred from each of these firms to two other firms, so that no one firm could unilaterally restrict output to spawn supra-competitive prices. The second feature explores how the presence of line constraints in a radial network may segment the market and promote supra-competitive pricing in the isolated market segments. We also consider the interaction effect when both of these structural features are present. Having established a wellcontrolled data set with price spikes paralleling those observed in the naturally occurring economy, we also extend the design to include demand-side bidding. We find that demand-side bidding completely neutralizes the exercise of market power and eliminates price spikes.

Stephen J. Rassenti; Vernon L. Smith; Bart J. Wilson

2003-01-01T23:59:59.000Z

434

Comparison on control strategies of the grid-side converter of variable speed constant frequency doubly-fed wind power generation system  

Science Conference Proceedings (OSTI)

Direct power control, vector control based on d-q synchronous rotating reference frame and ?-? static reference frame for the grid-side converter of variable speed constant frequency doubly-fed wind turbines are analyzed. System simulation ... Keywords: ?-? static reference frame, d-q rotating reference frame, direct power control, doubly-fed wind power generation system, grid-side converter

Xian-Ming Zhou; Ting-Long Pan; Zhi-Cheng Ji

2009-06-01T23:59:59.000Z

435

Modeling, control, and power management of a power electrical system including two distributed generators based on fuel cell and supercapacitor  

Science Conference Proceedings (OSTI)

This paper focuses on Distributed Generator (DG) integration in Power Electrical System (PES) for dispersed nodes. The main objective of the DG use can be classified into two aspects: a load following service and ancillary service systems. In this study

2013-01-01T23:59:59.000Z

436

Load controller and method to enhance effective capacity of a photovotaic power supply using a dynamically determined expected peak loading  

DOE Patents (OSTI)

A load controller and method are provided for maximizing effective capacity of a non-controllable, renewable power supply coupled to a variable electrical load also coupled to a conventional power grid. Effective capacity is enhanced by monitoring power output of the renewable supply and loading, and comparing the loading against the power output and a load adjustment threshold determined from an expected peak loading. A value for a load adjustment parameter is calculated by subtracting the renewable supply output and the load adjustment parameter from the current load. This value is then employed to control the variable load in an amount proportional to the value of the load control parameter when the parameter is within a predefined range. By so controlling the load, the effective capacity of the non-controllable, renewable power supply is increased without any attempt at operational feedback control of the renewable supply. The expected peak loading of the variable load can be dynamically determined within a defined time interval with reference to variations in the variable load.

Perez, Richard (Delmar, NY)

2003-04-01T23:59:59.000Z

437

Modeling and simulation of electric ships' power system components and their interaction  

Science Conference Proceedings (OSTI)

Models of propulsion motors, generators, gas turbines, and power converters are used to determine weights and volumes, evaluate designs, and predict performance of power system components for all-electric navy ships. The finite element analysis method ... Keywords: electric ships, permanent magnet generators, power rectifiers, propulsion motors

A. Ouroua; J. R. Jackson; J. H. Beno; R. C. Thompson; E. Schroeder

2007-07-01T23:59:59.000Z

438

Low cost power and supply noise estimation and control in scan testing of vlsi circuits  

Science Conference Proceedings (OSTI)

Test power is an important issue in deep submicron semiconductor testing. Too much power supply noise and too much power dissipation can result in excessive temperature rise, both leading to overkill during delay test. Scan-based test has ...

Zhongwei Jiang / Duncan Walker

2010-01-01T23:59:59.000Z

439

The potential role of nuclear power in controlling CO sub 2 emissions  

DOE Green Energy (OSTI)

Nuclear power currently reduces CO{sub 2} emissions from fossil fuel burning worldwide by about 8% (0.4 Gt(C)/yr). It can continue to play an important role only if it can grow substantially in the next 50 years. For such growth to occur public confidence will need to improve throughout the world. That might happen if (a) other non-fossil alternatives are inadequate to meet electricity demand growth, (b) the risks to society from global warming are perceived to be very high, (c) nuclear technology improves substantially, and (d) an international institutional setting is devised to manage the nuclear enterprise so that the technology is available to all nations while catastrophic accidents and proliferation of nuclear weapon capabilities are avoided. It seems feasible that the necessary technological and institutional advances can be devised and tested over the next 20 years. It is also plausible that the direct costs of electricity produced by the system would be in the range of 50-100 mills/kWhr (1990 dollars) delivered to the grid. In other words, the direct costs of nuclear power should not be greater than they are today. Achieving such an outcome will require aggressive technical and institutional RD D performed in a cooperative international setting. If rapid growth of nuclear power can begin again in 15-20 years it could supply 30-50% of world electricity in 50 years and cut CO{sub 2} emission rates by up to 2.5 Gt(C)/yr. This would be a substantial contribution to controlling greenhouse gases, but it is not sufficient. Improved efficiency and various renewable energy sources must also grow rapidly if CO{sub 2} emission rates from electricity generation are to be reduced from the current value of about 2 Gt(C)/yr. 41 refs., 4 figs., 3 tabs.

Fulkerson, W.; Jones, J.E.; Delene, J.G.; Perry, A.M.; Cantor, R.A.

1990-01-01T23:59:59.000Z

440

Real-time wind turbine emulator suitable for power quality and dynamic control studies, MASc Thesis  

E-Print Network (OSTI)

Abstract — Wind turbines are increasingly becoming significant components of power systems. To evaluate competing wind energy conversion technologies, a real-time Wind Turbine Emulator, which emulates the dynamic torque produced by an actual turbine has been developed. This is necessary since the real world performance of a wind turbine, subjected to variable wind conditions is more difficult to evaluate than a standard turbine generator system operating in near steady state. This emulator is capable of reproducing both the static and dynamic torque of an actual wind turbine. It models the torque oscillations caused by wind shear, tower shadow, and the obvious pulsations caused by variable wind speed. Also included are the dynamic effects of a large turbine inertia. This emulator will allow testing without the costly construction of the actual turbine blades and tower to determine the strengths and weaknesses of competing energy conversion and control technologies.

Dale S. L. Dolan; Student Member; P. W. Lehn; Member Ieee

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectifier power control" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Microminiaturized minimally invasive intravascular micro-mechanical systems powered and controlled via fiber-optic cable  

DOE Patents (OSTI)

A micro-mechanical system for medical procedures is constructed in the basic form of a catheter having a distal end for insertion into and manipulation within a body and a near end providing for a user to control the manipulation of the distal end within the body. A fiberoptic cable is disposed within the catheter and having a distal end proximate to the distal end of the catheter and a near end for external coupling of laser light energy. A microgripper is attached to the distal end of the catheter and providing for the gripping or releasing of an object within the body. A laser-light-to-mechanical-power converter is connected to receive laser light from the distal end of the fiberoptic cable and connected to mechanically actuate the microgripper.

Fitch, Joseph P. (Livermore, CA); Hagans, Karla (Livermore, CA); Clough, Robert (Danville, CA); Matthews, Dennis L. (Moss Beach, CA); Lee, Abraham P. (Walnut Creek, CA); Krulevitch, Peter A. (Los Altos, CA); Benett, William J. (Livermore, CA); Da Silva, Luiz (Danville, CA); Celliers, Peter M. (Berkeley, CA)

1998-01-01T23:59:59.000Z

442

Microminiaturized minimally invasive intravascular micro-mechanical systems powered and controlled via fiber-optic cable  

DOE Patents (OSTI)

A micro-mechanical system for medical procedures is constructed in the basic form of a catheter having a distal end for insertion into and manipulation within a body and a near end providing for a user to control the manipulation of the distal end within the body. A fiber-optic cable is disposed within the catheter and having a distal end proximate to the distal end of the catheter and a near end for external coupling of laser light energy. A microgripper is attached to the distal end of the catheter and providing for the gripping or releasing of an object within the body. A laser-light-to-mechanical-power converter is connected to receive laser light from the distal end of the fiber-optic cable and connected to mechanically actuate the microgripper. 22 figs.

Fitch, J.P.; Hagans, K.; Clough, R.; Matthews, D.L.; Lee, A.P.; Krulevitch, P.A.; Benett, W.J.; Silva, L. Da; Celliers, P.M.

1998-03-03T23:59:59.000Z

443

Electric Power Research Institute Environmental Control Technology Center Report to the Steering Committee  

Science Conference Proceedings (OSTI)

Operations and maintenance continued this month at the Electric Power Research Institute's (EPRI?s) Environmental Control Technology Center (ECTC). Testing for the month involved the Dry Sorbent Injection (DSI) test block with the Carbon Injection System. Also, several installation activities were initiated this month for the testing of a new EPRI/ADA Technologies sorbent sampling system in December. The 1.0 MW Cold-Side Selective Catalytic Reduction (SCR) unit, the 0.4 MW Mini Pilot Wet Scrubber, and the 4.0 MW Pilot Wet Scrubber remained idle this month in a cold-standby mode and were inspected regularly. These units remain available for testing as future work is identified.

None

1997-11-01T23:59:59.000Z

444

Electric Power Research Institute, Environmental Control Technology Center report to the Steering Committee. Final technical report  

Science Conference Proceedings (OSTI)

Operations and maintenance continued this month at the Electric Power Research Institute`s Environmental Control Technology Center. Testing on the 4.0 MW Pilot Wet FGD unit continued this month with the Trace Element Removal (TER) test block, and a simultaneous testing of the Lime Forced Oxidation process with DBA addition (LDG). At the end of the month, a series of Duct Injection tests began in a study to determine the efficiencies of alkaline injection for removing trace elements (mercury). On the Cold-Side Selective Catalytic Reduction (SCR) unit, low temperature performance testing continued this month as measurements were taken for NO{sub x} removal efficiency, residual ammonia slip, and SO{sub 3} generation across the catalysts installed in the SCR reactor. This report describes the status of the facilities and test activities at the pilot and mini-pilot plants.

NONE

1995-07-01T23:59:59.000Z

445

Emerging Technologioes in Instrumentation and Controls and Their Potential Regulatory Implications for Nuclear Power Plants  

Science Conference Proceedings (OSTI)

This paper provides a summary of eight instrumentation and control (&C) technology areas, with applications in nuclear power plants (NPPs), that were the focus of a recent study performed by Oak Ridge National Laboratory (ORNL) for the Nuclear Regulatory Commission (NRC.) The state of the technology s application in NPPs, along with potential regulatory impact(s), are discussed. The technology focus areas are: (1) sensors and measurement systems, (2) communications media and networking, (3) microprocessors and other integrated circuits, (4) computational platforms, (5) surveillance, diagnostics, and prognostics, (6) human-system interactions, (7) high-integrity software, and (8) I&C architectures in new plants. The regulatory implications of these focus areas with regard to their application in NPPs are also discussed.

Korsah, Kofi [ORNL; Bobrek, Miljko [ORNL; Cetiner, Mustafa Sacit [ORNL; Ewing, Paul D [ORNL; Holcomb, David Eugene [ORNL; Howlader, Mostofa [ORNL; Killough, Stephen M [ORNL; Kisner, Roger A [ORNL; Loebl, Andy [ORNL; Moore, Michael Roy [ORNL; Muhlheim, Michael David [ORNL; Mullens, James Allen [ORNL; Shourbaji, Ayman A [ORNL; Wilson, Thomas L [ORNL

2009-01-01T23:59:59.000Z

446

Aging Management Guideline for commercial nuclear power plants: Motor control centers; Final report  

SciTech Connect

This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in Boiling Water Reactor (BWR) and Pressurized Water Reactor (PWR) commercial nuclear power plant motor control centers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

Toman, G.; Gazdzinski, R.; O`Hearn, E. [Ogden Environmental and Energy Services Co., Inc., Blue Bell, PA (United States)

1994-02-01T23:59:59.000Z

447

Design and analysis of modern three-phase AC/AC power converters for AC drives and utility interface  

E-Print Network (OSTI)

Significant advances in modern ac/ac power converter technologies and demands of industries have reached beyond standard ac/ac power converters with voltage-source inverters fed from diode rectifiers. Power electronics converters have been matured to stages toward compact realization, increased high-power handling capability, and improving utility interface. Modern ac/ac power converter topologies with various control strategies have been introduced for the further improvements, such as matrix converters, current-fed converters, PWM rectifiers, and active power filters. In this dissertation, several new converter topologies are proposed in conjunction with developed control schemes based on the modern ac/ac converters which enhance performance and solve the drawbacks of conventional converters. In this study, a new fault-tolerant PWM strategy is first proposed for matrix converters. The added fault-tolerant scheme would strengthen the matrix converter technology for aerospace and military applications. A modulation strategy is developed to reshape output currents for continuous operation, against fault occurrence in matrix converter drives. This study designs a hybrid, high-performance ac/ac power converter for high power applications, based on a high-power load commutated inverter and a mediumpower voltage source inverter. Natural commutation of the load commutated inverter is actively controlled by the voltage source inverter. In addition, the developed hybrid system ensures sinusoidal output current/voltage waveforms and fast dynamic response in high power areas. A new topology and control scheme for a six-step current source inverter is proposed. The proposed topology utilizes a small voltage source inverter, to turn off main thyristor switches, transfer reactive load energy, and limit peak voltages across loads. The proposed topology maximizes benefits of the constituent converters: highpower handling capability of large thyristor-based current source inverters as well as fast and easy control of small voltage source inverters. This study analyzes, compares, and evaluates two topologies for unity power factor and multiple ac/ac power conversions. Theoretical analyses and comparisons of the two topologies, grounded on mathematical approaches, are presented from the standpoint of converter kVA ratings, dc-link voltage requirements, switch ratings, semiconductor losses, and reactive component sizes. Analysis, simulation, and experimental results are detailed for each proposed topology.

Kwak, Sangshin

2006-05-01T23:59:59.000Z

448

A New Wind Turbine Control Method to Smooth Power Generation. Modelling and Comparison to Wind Turbine Frequency Control.  

E-Print Network (OSTI)

??Following the significant increase of world wide installed wind power during the first decade of the 21st century, transmission system operators are faced with new… (more)

Solberg, Olov

2012-01-01T23:59:59.000Z

449

Nitrogen oxides emission control through reburning with biomass in coal-fired power plants  

E-Print Network (OSTI)

Oxides of nitrogen from coal-fired power stations are considered to be major pollutants, and there is increasing concern for regulating air quality and offsetting the emissions generated from the use of energy. Reburning is an in-furnace, combustion control technology for NOx reduction. Another environmental issue that needs to be addressed is the rapidly growing feedlot industry in the United States. The production of biomass from one or more animal species is in excess of what can safely be applied to farmland in accordance with nutrient management plans and stockpiled waste poses economic and environmental liabilities. In the present study, the feasibility of using biomass as a reburn fuel in existing coal-fired power plants is considered. It is expected to utilize biomass as a low-cost, substitute fuel and an agent to control emission. The successful development of this technology will create environment-friendly, low cost fuel source for the power industry, provide means for an alternate method of disposal of biomass, and generate a possible revenue source for feedlot operators. In the present study, the effect of coal, cattle manure or feedlot biomass, and blends of biomass with coal on the ability to reduce NOx were investigated in the Texas A&M University 29.31 kW (100,000 Btu/h) reburning facility. The facility used a mixture of propane and ammonia to generate the 600 ppm NOx in the primary zone. The reburn fuel was injected using air. The stoichiometry tested were 1.00 to 1.20 in the reburn zone. Two types of injectors, circular jet and fan spray injectors, which produce different types of mixing within the reburn zone, were studied to find their effect on NOx emissions reduction. The flat spray injector performed better in all cases. With the injection of biomass as reburn fuel with circular jet injector the maximum NOx reduction was 29.9 % and with flat spray injector was 62.2 %. The mixing time was estimated in model set up as 936 and 407 ms. The maximum NOx reduction observed with coal was 14.4 % and with biomass it was 62.2 % and the reduction with blends lay between that of coal and biomass.

Arumugam, Senthilvasan

2004-12-01T23:59:59.000Z

450

The design of new wind power controller based on Superconducting Magnetic Energy Storage  

Science Conference Proceedings (OSTI)

The fluctuation and intermittent with wind power output, as a key factor to connect a large-scale wind power system to grid, which result s in an adverse impact on the power system continues to grow. In order to reduce the net stability impact of the ... Keywords: Wind Farm, Superconducting Magnetic Energy Storage, Wind Power, Applied Superconductivity

Zhou Xue-Song; Quan Bo; Ma You-Jie; Wu Le

2010-08-01T23:59:59.000Z

451

Memory Controller Policies for DRAM Power Management Xiaobo Fan Carla S. Ellis Alvin R. Lebeck  

E-Print Network (OSTI)

to transition back to active. Energy e ciency can be improved by placing the chips in a lower power state when spent in the current power state before a transition to a lower state is made. We refer management policies. #12;Power State Power Time Transition mW nS Active Pa = 300 tacc=60 Standby Ps = 180

Lebeck, Alvin R.

452

Run-Time Power-Down Strategies for Real-Time SDRAM Memory Controllers  

E-Print Network (OSTI)

. PDTRANS PUP Figure 1: Power-Down Transitions 3.3 Arbiters and Latency-Rate Servers Real-time SDRAM memory on the memory state and the power- down duration, for both the power-down strategies. We experimentally evaluate, the tTRANS parameter gives the transition in timing constraint before the memory can switch to a power

Epema, Dick H.J.

453

Memory Controller Policies for DRAM Power Management Xiaobo Fan Carla S. Ellis Alvin R. Lebeck  

E-Print Network (OSTI)

to transition back to active. Energy efficiency can be improved by placing the chips in a lower power state when spent in the current power state before a transition to a lower state is made. We refer management policies. #12; Power State Power Time Transition (mW) (nS) Active Pa = 300 tacc=60 Standby Ps

Lebeck, Alvin R.

454

Viscosity virtual sensor to control combustion in fossil fuel power plants  

Science Conference Proceedings (OSTI)

Thermo-electrical power plants utilize fossil fuel oil to transform the calorific power of fuel into electric power. An optimal combustion in the boiler requires the fuel oil to be in its best conditions. One of fuel's most important properties to consider ... Keywords: Automatic learning, Bayesian networks, Fuel oil, Power plants, Virtual sensors

Pablo H. Ibargüengoytia, Miguel Angel Delgadillo, Uriel A. García, Alberto Reyes

2013-10-01T23:59:59.000Z

455

Optimal control of remote hybrid power systems. Part 1: Simplified model  

SciTech Connect

In this two-part study, time-series models are used to determine optimal dispatch strategies, in conjunction with optimally-sized components, in remote hybrid power systems. The objective of the dispatch optimization is to minimize the costs associated with diesel fuel, diesel starts, and battery erosion, based on a thorough economic analysis of present worth life-cycle cost. An ideal predictive control strategy is used as a basis of comparison. In Part 1 (reported here), a simplified time-series model is used to obtain preliminary conceptual results. These results illustrate the nature of the optimal dispatch strategy and indicate that a simple SOC setpoint strategy can be practically as effective as the ideal predictive control. In Part 2 (at a later date), a more detailed model will be used to obtain more accurate, quantitative results. The authors anticipate that these results will be correlated to dimensionless economic, design, and performance parameters, rendering them useful as design guidelines over a wide variety of load profiles, climates, equipment specifications, and economic variables.

Barley, C D [Colorado State Univ., Fort Collins, CO (United States). Mechanical Engineering Dept.; [National Renewable Energy Lab., Golden, CO (United States). Wind Technology Div.; Winn, C B [Colorado State Univ., Fort Collins, CO (United States); Flowers, L; Green, H J [National Renewable Energy Lab., Golden, CO (United States). Wind Technology Div.

1995-04-01T23:59:59.000Z

456

Tools, Methods, and Modeling for Dynamic Distribution Systems, Power Factor Guidelines: Power Control with Distributed Energy Resources  

Science Conference Proceedings (OSTI)

With the onset in the past few years of tax incentives, subsidies, and renewable portfolio standards for distributed energy resources (DER), utilities are experiencing increasing numbers of interconnection requests for both large, MW-class systems as well as small, residential-scale systems. As a result, utilities need methods for integrating DER without impacting system reliability or power quality for other customers, while also maintaining flexibility for future changes and minimizing ...

2013-12-19T23:59:59.000Z

457

EPRI Comments on a UK Case-Control Study of Magnetic Fields from High Voltage Power Lines and Childhood Cancer  

Science Conference Proceedings (OSTI)

A paper, entitled "Childhood cancer and magnetic fields from high voltage power lines in England and Wales: a case-control study," was published in the British Journal of Cancer on September 28, 2010. The authors assessed the association between exposure to EMF from power lines at the address of birth and childhood cancer. The current paper provides additional results to a study published earlier from the same data set in 2005. These EPRI comments provide an overview of study findings, conclusions, stren...

2010-12-22T23:59:59.000Z

458

Sensing system for detection and control of deposition on pendant tubes in recovery and power boilers  

DOE Patents (OSTI)

A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions of about 4 or 8.7 microns and directly producing images of the interior of the boiler, or producing feeding signals to a data processing system